GGSPro Tech Tips

Cyco Killer: How to Diagnose and Defend Against Fusarium Wilt in Cyclamen

Fusarium species are found worldwide as plant pathogens and saprophytes (a fungus living on dead or decaying organic matter). Losses to plants are most commonly from a vascular wilt affecting various crops grown in greenhouses: basil, begonia, carnation, cyclamen, exacum, lisianthus, pepper and tomato. Since 1997, new wilts have been detected in argyranthemum, osteospermum, chrysanthemum and gerbera. Here, we’ll focus specifically on Fusarium in cyclamen.


Bright yellow leaf chlorosis is a common first symptom
of Fusarium wilt in cyclamen.
As cyclamen is quite a long crop, it’s to the dismay of growers that Fusarium symptoms often aren’t apparent until the plants begin to flower. Only a small percentage of plants show symptoms at transplant, roughly three months after germination. However, after 30 weeks, 34-71% plants can be infected.

When signs do become visible, the most common symptom in young cyclamen plants is a bright-yellow leaf chlorosis beginning at the leaf base, often on one side of the plant. Leaves generally remain turgid. As symptoms progress, leaves flop as stalks are weakened and older leaves turn brown.


Discoloration in the vascular bundles of the cyclamen corm
Below the surface, young plants’ root systems may show vascular discoloration or turn dark brown to brownish black. Corms remain hard but when cut horizontally, the presence of discoloration in the vascular bundles can be observed on one side, increasing in severity as the plant matures. If humidity and temperature levels are ideal, white to pinkish fruiting bodies may develop at the base of the tuber on the stems.

Environmental stresses can hasten the development of Fusarium wilt in cyclamen. Drought and extreme heat are among the most commonly reported triggers.

Fusarium enter and spread in the greenhouse through spores, which infect plants through roots via wounds or natural openings. Over a period of 2-13 weeks, the fungus works its way up through the roots, into the vascular system of the tuber into the plant.

In general, Fusarium sp. can survive on seed coats, on corms/bulbs, in roots, in irrigation water, in irrigation equipment and pipes, via spores in air movement and insect transmission (fungus gnats and shoreflies).

When it comes to managing Fusarium risk, of course, the best defense is a good offense. Fusarium management should begin with good sanitation practices at the beginning of production. Sources of inoculum over which growers have direct control include the use of infected soil, which allows the pathogen to harbor in weeds and compost piles, as well as reusing infected pots and trays.

When it comes to managing Fusarium risk, of course, the best defense is a good offense. Fusarium management should begin with good sanitation practices at the beginning of production.

Fusarium can survive on various surfaces including wood, concrete and polyethylene film. Strip-It followed by KleenGrow is very effective on all three surfaces. Other effective products include GreenShield II or SaniDate 5.0.

Containers should provide good drainage, containing 15-30% perlite, such as Premier ProMix HP or BK25, while avoiding heavy peat media. Trays should support pots, but create air space between the tray and ground.

Conditions become optimum for pathogen development in cyclamen at 82°F. Temperatures above 86°F increase severity due to excessive transpiration that occurs, while development slows at lower temperatures. Plants should be shaded to keep temperature under 73°F. Avoid fertilizing with ammonical sources of nitrogen, and maintain a soil pH above 5.8.

Once a plant is attacked, it’ll fail to become marketable and should be removed immediately. The practice of drenching remaining asymptomatic plants alone with fungicides has not proven to be 100% successful, and can take a toll on the remaining plants, so this approach should be used only as a last resort.

Fungicides labeled for Fusarium include: Banrot, Cleary’s 3336, Medallion/Emblem, Terraguard and strobiluron-based fungicides such as Empress Intrinsic, Fame SC, Heritage, Mural, Orkestra Intrinsic and Pageant Intrinsic drenches.

Plant protection is often implemented with the addition of biofungicides to protect crops against Fusarium wilt. These include Actinovate, Companion, RootShield, RootShield Plus and PreFence. Research studies continue to enhance the benefits of pairing biological fungicides with registered fungicides to yield significant reduction in Fusarium disease development.

Product NameMOADescriptionItem Number
Chemical Fungicides
Banrot 40% WP
1 + 14
2 lbs
71-1210
Banrot 8G
1 + 14
40 lbs
71-1215
Cleary’s 3336F
1
1 qt
71-2575
Cleary’s 3336 EG
1
5 lb
71-2550
Emblem/Spirato
12
1 pt
71-1570
Empress Intrinsic
11
24 oz
70-1510
Fame G
11
25 lbs
71-1500
Fame SC
11
16 oz
71-1505
Heritage
11
4 oz
71-1404
Medallion WDG
12
8 oz
71-16502
Mural WG
43411
1 lb
71-1690
OHP 6672 L
1
2.5 gal
71-2670
OHP 6672 WSP
1
2 lbs
71-2672
Orkestra Intrinsic
43411
16 oz
71-2200
Pageant Intrinsic
43411
1 lb
71-26801
Terraguard SC
3
1 qt
71-3018
Biological Fungicides
Actinovate
NC
18 oz
31007318
Companion
44
1 gal
71-1375
RootShield WP
NC
1 lb
71-2789
RootShield G
NC
10 lbs
71-2780
RootShield Plus G
NC
10 lbs
71-27911
RootShield Plus WP
NC
1 lb
71-27951
PreFence
NC
5 gm
71-2770
Sanitation Products
Greenshield II
30 gal
74-36611
KleenGrow
5 gal
74-21151
SaniDate 5.0
2.5 gal
71-35001
Strip-It Pro
5 gal
74-2125
ZeroTol
NC
2.5 gal
71-35501
Printable version

The Microbes Move In: A Compelling Case for Biological Fungicides

The wet, cool wet spring of 2018 gave growers ample reason to apply a fungicide. At some points, the GGSPro technical services team could have answered the phones with, “Botrytis Central. How can we help?” To be sure, we recommended applications of traditional foliar fungicides to many, many growers of ornamentals during that time.

Times of heavy disease pressure, like this spring, can make it difficult to choose and rotate the proper fungicides. Growers may be tempted to skimp, using fewer products at a lower investment than the recommended full rotation of at least three products, which is known to delay chemical resistance.

This is just one situation wherein biological fungicides really show their utility! Read on to see how. If you grow organic and/or edible crops, you may already rely heavily on the use of microbial fungicides, but please continue reading to learn how these products work and to see the latest introductions in this class.



Microbial fungicides have broad labels allowing them to be used on all ornamentals and almost all edible crops. The list of diseases controlled is often broad, further increasing the products’ utility.


    The “why” of biological fungicides

    So why might a grower, with all the chemical options available to them, choose a fungicide based on a bacterium or fungus?

    1. Microbial fungicides have broad labels allowing them to be used on all ornamentals and almost all edible crops. The list of diseases controlled is often broad, further increasing the products’ utility.
    2. A reduced risk of pesticide resistance is expected, due to the modes of action of these microbial fungicides. Furthermore, using biologicals helps to preserve the activity of traditional chemicals, by reducing how often they’re needed and used.
    3. All of these fungicides have short re-entry intervals (REIs) and modest amounts of personal protection equipment (PPE) are required. These facts signal their relative human safety and make them easier to use.
    4. The costs are reasonable; there’s no premium for the advantages listed above.
    5. Lastly, the buying public wants our industry to use the safest products available. These products fit that charge.


    The “how” of biological fungicides

    How do biological fungicides work? Often, the organisms work through more than one mode of action, a helpful trait in terms of fending off pesticide resistance. ‘Fending off’ is an apt description for some of the more common modes of action, which include:
    • Antibiotic: The organism produces compounds that inhibit the plant pathogens. E.g., compounds that inhibit fungal and bacterial spores from germinating.
    • Competition: The beneficial organism depletes the treated area of resources needed by the pathogen and thereby out-competes it for that location.
    • Exclusion: In this case, the beneficial organism populates the surface of the plant tissue, growing and physically excluding the pathogen.
    • Parasitism: The beneficial organism feeds directly on the pathogen, inhibiting it or killing it altogether.
    • Induced resistance: The organism activates signaling pathways in the plant, leading to an immune-like response in the plant.

    Product NameMicrobial FungicidesMOADescribed MOAShelf LifeOMRI-listedItem Number
    Actinovate SP T&O
    Streptomyces lydicus WYEC
    NC
    Antibiotic
    Exclusion
    Parasitism
    18 months
    Yes
    31007318 (temporarily unavailable)
    BotryStop
    Ulocladium oudemansii U3 strain
    UN
    Competition
    Exclusion
    12 months refrigerated
    Yes
    71-1260
    Cease
    Bacillus subtilis QST 713 strain
    44
    Antibiotic
    Competition
    Parasitism
    Induced resistance
    2 years
    Yes
    71-13301
    Companion
    Bacillus subtilis strain GB03
    44
    Antibiotic
    Competition
    Parasitism
    2 years
    No
    71-1375
    Triathlon BA
    Bacillus amyloliquefaciens strain D747
    44
    Antibiotic
    Competition
    Parasitism
    2 years kept cool
    Yes
    71-3040



    Mode of action (MOA) 44 indicates the fungicide disrupts the integrity of the pathogen’s cell membrane. MOA NC is “Not Classified.” MOA UN is “Unknown;” as the mechanisms are defined, these MOAs will be reassigned.


    PVent is a new microbial fungicide soon to be released by BioSafe. It’s based on a unique strain of Gliocladium fungus and will be registered for many foliar diseases including Botrytis. Rick Yates, GGSPro technical services manager, will be covering PVent in detail at the 2018 Griffin Expos in his “Hot Topics in Pest Control” seminar. Click here to learn more and register to join us in Worcester, Mass., or Lancaster, Penn.!


    Other attributes microbial fungicides hold in common:

    • These products are considered primarily preventative fungicides.
    • When treating an active infection, when possible, use a knock-down product followed by the microbial.
    • Tank-mixing is possible with a wide selection of other fungicides and insecticides.
    • Do not tank-mix with fungal-based insecticides (e.g., Ancora, BioCeres, BotaniGard).
    • Do not tank-mix with a bactericide, except as allowed on the label.
    • These products have excellent plant and bloom safety.
    • With the exception of BotryStop, products are also labeled for root and crown rot drench applications.

    To ensure maximum success with these microbial fungicides, first compare labels to confirm they’re suitable for the diseases you wish to control. They’re relatively short-lived on leaf surfaces, so pay close attention to re-application intervals and apply before disease is active.
    As with other types of fungicides, it’s essential to manage the growing environment to minimize disease pressure. The best fungicides will fail if growing conditions are favorable for disease development. GGSPro can provide electronic labels upon request. We’re also available to assist with your pest-control decisions.

    Printable version

    Feed Me, Seymour! A Modern Guide to Garden Mum Nutrition

    Cheryl garden mum family,
    photo credit: Syngenta Flowers, LLC
    Fall garden mums are an important revenue source for many professional ornamental growers. While traditional production methods can yield a good crop, adopting a newer philosophy can help growers produce strong, uniform and well-branched plants with greater predictability.


    Fertilizer philosophy

    The ideal soil pH for garden mums is 5.4-5.8. Depending on the alkalinity of the water source, acid-forming fertilizers or sulfuric acid injection may be helpful to keep soil pH in the desired range. Growers solely using controlled-release fertilizer (CRF) will need to rely on acid injection for high-alkalinity water sources. GGSPro can help direct you with these decisions.

    Garden mum fertility can be achieved through CRF, water-soluble fertilizer (WSF) or a combination of the two, which GGSPro refers to as the half-and-half approach. For growers using overhead irrigation, a CRF program is often more efficient. Growers using drip irrigation tend to prefer WSF. A half-and-half approach provides both flexibility to adjust the fertility program and protect against leaching from rains, as CRF provides a constant supply of fertility. Any use of CRF requires the use of WSF in the initial two weeks to meet the heavy nutritional needs of the crop, and to encourage soft growth to support maximum branching.

    Mum crops achieve optimum plant structure due to significant branching early in the crop. To encourage this free branching, growers should encourage soft growth in the first 2-3 weeks of production. This is best achieved via fertilizers that provide more phosphorus than we normally use for the rest of the crop cycle. Regardless of the fertility program selected, all mums should be irrigated with a 20-20-20 or 20-10-20 WSF during the first 2-3 weeks of production.


    Recommended fertility programs for garden mum production

    TimingWSF OnlyHalf-and-HalfCRF Only
    First irrigation
    300 ppm
    250 ppm
    300 ppm

    Planting to week 2
    300 ppm constant feed
    250 ppm constant feed
    300 ppm once per week

    Week 3 to first color
    200-250 ppm constant feed
    300 ppm once per week
    Clear water

    First color to sale
    100 ppm constant feed
    Clear water
    Clear water


    For the main part of the crop, growers using WSF-only or half-and-half programs should switch to a lower phosphorus formulation, such as a 20-10-20 and rotate with a fertilizer that contains calcium, such as a 15-0-15. The rate and frequency of application during this time should be reduced from the early rates.

    A rotation of 3-4 applications of the acid fertilizer to one application of the calcium feed is recommended. This 3-4:1 rotation will provide adequate calcium for later stem strength while allowing proper management of the media pH. The rotation may need to be adjusted based on the alkalinity of the irrigation water. Regardless of the alkalinity, the important thing is to provide adequate calcium to the crop during this phase of production.


    Pumping iron

    Mums aren’t particularly efficient at taking up iron and are quick to show symptoms of iron deficiency. As media pH rises above the ideal range, the availability of iron decreases.
    Iron deficiency symptoms begin with interveinal yellowing of the youngest foliage in the growing tips. Mum varieties vary somewhat in their threshold for showing iron deficiency, so it’s common to see the problem begin in just a few varieties, progressing through the field if corrective measures aren’t taken.

    Iron deficiency in garden mum
    Adjusting the soil pH down to the ideal range is the first step in preventing or correcting iron deficiency. If necessary, chelated iron can be applied to correct the issue. Sprint 138 or 330 can be applied as a drench at 4-5 oz per 100 gallons. GGSPro doesn’t recommend foliar sprays or dry treatments to the soil because of the increased potential for phytotoxicity.
    Never apply chelated iron to plants under water stress. Always rinse the foliage with clear water following application of iron to avoid a pitting burn, which can occur if the solution is allowed to dry on the foliage.


    More magnesium

    High soluble salts burn on garden mum
    Mums also benefit from additional magnesium. One of magnesium’s key roles is in the photosynthesis process of chlorophyll production, which makes leaves green. Magnesium is most easily provided with Epsom salts. For constant application, use 2 oz of Epsom salts per 100 gallons, along with your non-calcium-based fertilizer. Alternatively, pulse treatments of 8 oz per 100 gallons on a biweekly basis, or as needed. Magnesium deficiency in mums appears as an interveinal chlorosis of the lower (older) leaves.

    Mums are heavy feeders, but they’re still susceptible to damage from high soluble salts. The most common causes of high-salts damage are drought and applying fertilizer to overly dry media. Both situations result in the plant perceiving a very high salts gradient in the root zone, leading to damage on the foliage. Avoid drought stress and always ensure adequate soil moisture at the time of fertilizer application.






    Product Name
    Description
    Item Number
    EVERRIS 20-20-20 General Purpose Base Formulation
    20-20-20, 25 lbs
    67-2318
    Jacks WSF 20-20-20 General Purpose
    20-20-20, 25 lbs
    33612
    Plantex 20-20-20 Classic
    20-20-20, 25 lbs
    31-140300
    EVERRIS 20-10-20 Peat Lite Special Base Formulation
    20-10-20, 25 lbs
    67-2332
    Jack's WSF 20-10-20 Peat-Lite
    20-10-20, 25 lbs
    33615
    Plantex 20-10-20 All Purpose High Nitrate
    20-10-20, 25 lbs
    31-140200
    EVERRIS 21-5-20 Excel Multi Purpose Base Formulation
    21-5-20, 25 lbs
    67-2308
    Jack's WSF LX 21-5-20 All Purpose
    21-5-20, 25 lbs
    33602
    Plantex 21-5-20 All Purpose High Nitrate WSF
    21-5-20, 25 lbs
    31-140306
    EVERRIS 15-0-15 Peat Lite Dark Weather Feed
    15-0-15, 25 lbs
    67-2340
    Jack's WSF 15-0-15 Dark Weather Peat-Lite
    15-0-15, 25 lbs
    33627
    Plantex 15-0-15 Cal-Plus
    15-0-15, 25 lbs
    31-140100
    Epsom Salts
    50 Lbs
    14MGSUL
    Florikote 12-4-11: 100 day
    12-4-11, 50 lbs
    33-12411100
    Nutricote 13-11-11: 100 day
    13-11-11, 50 lbs
    32-200129
    Osmocote Plus 15-9-12: 8-9 month
    15-9-12, 50 lbs
    67-1540
    Sprint 330
    5 lbs
    67-70371
    Sprint 138
    5 lbs
    67-7036

    Printable version

    Thrips Threat: How to Defeat Western Flower Thrips in Peak Season

    Thrips feeding damage on chrysanthemum flower
    Image credit: Bioline AgroSciences
    Many growers enter each season with swords drawn, anticipating another fight to the finish with western flower thrips (WFT). Rampaging thrips can blaze a devastating trail of scarred blooms, deformed leaves and spread tospoviruses.

    GGSPro remains strong proponents of biological control for insect and mite pests, including thrips. However, this time of year is no time to begin a biological control program: Thrips are already active and reproductive rates are very high. For that reason, our focus today is on pesticides for thrips control. Long before you plan for your next spring crop, you can consult with GGSPro about an integrated pest management program that includes scouting, exclusion, sanitation, rotating pesticides and BCAs.



    This time of year is no time to begin a biological control program: Thrips are already active and reproductive rates are very high.
    Thrips have a well-earned reputation for developing resistance to pesticides. Practicing a sound rotation strategy is key to slowing the progression of pesticide resistance. GGSPro works closely with many growers regarding pest control programs, gaining continuous and valuable insight into which products are working well and how best to utilize them.
    Western flower thrips adult

    The products and application strategies outlined below are currently among the most successful for thrips control. Many factors in addition to efficacy may influence product selection, including: rotational planning, bee safety, compatibility with BCAs, plant and bloom safety, label requirements for edible crops and more. Contact GGSPro for recommendations tailored to your unique situation and needs.




    Table 1: The following products control WFT effectively from a soil drench

    Product NameMOARateCommentsItem Number
    Kontos
    23
    1.7-3.4 oz/100 gal
    Contact GGSPro for customized drench recipes. Requires 2-3 weeks to take full effect, provides 4 weeks or more of control. No geranium, dracaena, cordyline, palm, fern, hoya, phlox. Some reports of discolored verbena flowers. Zero-hour REI from a drench if conditions are met.
    70-19601
    Mainspring GNL
    28
    8-12 oz/100 gal or 0.5-0.75 tsp/gal
    Takes 1 week or less for full effect, provides 4 weeks or more of control. Restricted-use pesticide in NY. Zero-hour REI from a drench if conditions are met.
    70-2331


    Table 2: The following products control WFT effectively from a foliar spray 



    Product Name
    MOARateCommentsItem Number
    Mainspring GNL
    28
    4-8 oz/100 gal or 0.25-0.5 tsp/gal
    Restricted-use pesticide in NY. 4-hour REI.
    70-2331
    Mesurol 75 WP
    1A
    1 lb/100 gal or 1 Tbls/gal
    Leaves residue; safe on most open blooms. Maximum of 2 applications at least 10 days apart. Restricted-use pesticide. 24-hour REI.
    70-2325
    Overture 35 WSP
    UN
    2 oz/25 gal Cannot open packets
    Takes up to 6-7 days to evaluate control. Up to 2 weeks control. Greenhouse applications only. 12-hour REI.
    70-2590
    Pedestal SC
    15
    8 oz/100 gal or 0.5 tsp/gal
    Insect growth regulator. Max of one application in 30 days and 2 treatments per crop/year. Must rotate two alternative products between applications. 12-hour REI.
    70-2950
    Pylon
    13
    5.2 oz/100 gal or 0.33 tsp/gal
    Make 2 applications at 5-7 day intervals. Maximum 3 times per crop. No dianthus, kalanchoe, poinsettia, rose, salvia, zinnia. May burn tender blooms, test prior to use. Greenhouse use only. Restricted-use pesticide in NY. 12-hour REI.
    70-2675
    Pylon TR
    13
    1 can treats 3,000 sq ft
    Total release aerosol. See Pylon above for crop restrictions. Greenhouse application only. Restricted-use pesticide in NY. 12-hour REI.
    70-2660

    Tank mixes can sometimes be used to successfully control WFT. Some examples include: Avid plus azadirachtin (neem)-based insect growth regulators such as Azatin O, AzaGuard or Molt-X. Two sprays, 7 days apart before rotating to another MOA. 
    Thrips feeding damage on gerbera flower
    Image credit: Bioline AgroScience

    Beauveria bassiana
    -based insecticides such as Bioceres, Botanigard ES, WP plus azadirachtin (neem)-based insect growth regulators (see above) or horticultural oils such as Suffoil-X or Ultra-Pure oil. Ancora is a microbial insecticide/miticide-based Isaria fumosorosea Apopka Strain 97 and it can be used in place of one of the Beauveria bassiana products. GGSPro recommends a series of three sprays, 3-5 days apart. The first and third sprays in the series are a tank mix of the microbial insecticide and either one the azadirachtin (neem)-based insect growth regulators or the horticultural oil. The second treatment in the series is just the microbial insecticide. These sprays have the advantage of being approved for many edible crops. Certain combinations are OMRI-listed, too.



    Table 3: The following insecticides can be used to make the tank mixes listed above

    Product NameMOARateCommentsItem Number
    Ancora
    UN
    28 oz/100 gal or 1 Tbls/gal
    Use the decant procedure found on the Ancora technical bulletin to avoid clogging application equipment. 4-hour REI, OMRI-listed.
    70-1166
    Avid
    6
    8 oz/100 gal or 0.5 tsp/gal
    Do not use on Shasta daisy, ferns. 12-hour REI.
    70-1185
    Azatin O
    UN
    10.66 oz/100 gal or 0.66 tsp/gal
    4-hour REI, OMRI-listed.
    70-12301
    AzaGuard EC
    UN
    8 oz/100 gal or 0.75 tsp/gal
    4-hour REI, OMRI-listed.
    70-1224
    BioCeres WP
    UN
    30 oz/100 gal or 2 tsp per gal
    4-hour REI, OMRI-listed.
    70-1245
    BotaniGard ES
    UN
    2 qt/100 gal or 4 tsp/gal
    Do not use on tomatoes. 4-hour REI.
    70-12501
    BotaniGard 22WP
    UN
    2 lb/100 gal or 4 tsp/gal
    Improved BCA safety compared to the ES formulation. Safe for tomatoes. 4-hour REI.
    70-12521
    Molt-X
    UN
    10 oz/100 gal or 0.66 tsp/gal
    4-hour REI, OMRI-listed.
    70-2400
    SuffOil-X
    UN
    1 gal/100 gal or 1.25 oz/gal
    Thorough coverage needed. Apply when rapid drying will occur for plant safety. May burn open blooms. 4-hour REI, OMRI-listed.
    70-4040
    Ultra-Pure Oil
    UN
    1 gal/100 gal or 1.25 oz/gal
    Thorough coverage needed. For plant safety, apply when rapid drying will occur. May burn open blooms. 4-hour REI.
    70-21401

    It is applicator’s responsibility to read and follow all pesticide label instructions. Labels can and do change without notice. Not all of the products mentioned in this bulletin are registered for use in all states. Some pesticides are restricted-use in some states or regions and not others. Contact GGSPro or your state’s Department of Agriculture to verify registration status. Pesticides other than those mentioned may be safe and effective.

    Printable version

    Blight Risk: What to Do When Good Tomatoes Go Bad

    It’s that time of year: Gardeners coast-to-coast are starting tomato seedlings in anticipation of the first red tomato of the season. Commercial growers offer an assortment of varieties with various colors, flavors, sizes and harvest times to meet just about every tomato lover’s palate.

    Many of today’s cultivars are bred with inherent disease resistance for Fusarium (F), Verticillium (V), Nematode (N), Tobacco Mosaic Virus (TMV), Tomato Spotted Wilt Virus (TSWV), Alternaria Leaf Spot (ALS) and/or Grey Leaf Spot (GLS), among others. Look for tomato varieties with one or more of these resistance packages. You can find these codes among the tomato offering in the Griffin Seed & Plant catalog, for example, to indicate resistance to these and other plant pathogens.

    Keep in mind, however, that resistance does not imply immunity! If conditions that promote these diseases are favorable, resistant plants will perform better than those without resistance but infection is still possible. Many conditions such as rainfall, soil conditions, temperatures and humidity can influence disease pressure.

    The most common and destructive plant foliar diseases may be treated if they’re identified before overtaking the plant. The key to preventing or reducing the severity of tomato diseases is to monitor plants weekly, looking for symptoms on leaves and fruit, and by understanding key environmental factors and cultural practices to follow.


    Not all of the products mentioned here are registered for use in all states. Some pesticides are restricted-use in some states or regions, but not others. Contact GGSPro with product-specific questions. Always read and follow product label instructions. Pesticide labels contain more essential information than can be included here, including Personal Protection Equipment (PPE), special precautions, maximum yearly application rates and more. Information in this bulletin is believed to be correct, however, labels do change without notice. Pesticides other than those listed may be safe, legal and effective.

    Image credits:
    Early Blight foliage photo – Steve Bogash
    Early Blight fruit photo – T.A. Zitter, Cornell University
    Septoria fruit photo – Bruce Watt, University of Maine

    ProductMOADescriptionItem Number
    Affirm
    19
    0.5 lb
    30F50
    Alude
    33
    2.5 gal
    30F250
    Camelot O
    M1
    1 gal
    30F5T
    Cease
    44
    2.5 gal
    SB1011-02
    Emblem/Spirato
    12
    1 pt
    SB1011-03
    Fosphite
    33
    1 gal
    70-2460
    Milstop
    NC
    5 lb
    70-2490
    Nordox
    M1
    12.5 lb
    70-6033
    Phyton 35
    M1
    1 ltr
    70-6034
    Protect DF
    M3
    6 lb
    70-6037
    Ranman
    21
    1 qt
    70-7025
    Regalia
    P5
    1 gal
    70-7035
    Subdue MAXX
    4
    1 qt
    70-7050
    Triathlon BA
    44
    1 gal
    70-7050
    Printable version

    Under Siege! Scouting and Control Tips to Combat the Able Aphid

    Aphids are a pest of economic significance to both ornamental and edible crops, with roughly 5,000 known aphid species living around the world. Some aphid types only feed on a specific plant genus, like crepe myrtles or hops, but the vast majority of aphids are far less selective.

    Plants known to be prone to aphids include ageratum, alyssum, aster, celosia, chrysanthemum, dahlia, Easter lily, gerbera, herbs, fuchsia, hydrangea, impatiens, mandevilla, pansy, pepper, portulaca, primula, salvia, snapdragon, tomato, verbena and zinnia. If this list sounds like your spring production plan, please read on. If not, you may still want to continue.



    Practically speaking, no spring crop is immune to aphid infestation – some are just less favored. It’s good to be prepared.

    Once you know that 260 species of aphids have been documented on artemesia alone, you may wonder if (and when) your crops will get aphids this year. Practically speaking, no spring crop is immune to aphid infestation – some are just less favored. It’s good to be prepared.

    Aphids attack all above-ground plant parts. In addition, some aphid types also feed on roots or bulbs. Aphids gives birth to live young, without the need for fertilization. As aphid nymphs settle in for their first meal, they already have the next generation developing within them.

    When aphids sense overcrowding or the need to move to another food source, they give birth to winged aphids that efficiently disperse to more distant plants. Once they’ve spread out, they go back to producing progeny with no wings. 


    Aphids attack all above-ground plant parts. In addition, some aphid types also feed on roots or bulbs. Aphids gives birth to live young, without the need for fertilization. As aphid nymphs settle in for their first meal, they already have the next generation developing within them.

    When aphids sense overcrowding or the need to move to another food source, they give birth to winged aphids that efficiently disperse to more distant plants. Once they’ve spread out, they go back to producing progeny with no wings. 


    Winged and wingless green peach aphids
    Image credit: Whitney Cranshaw



    The reproductive rate of aphids is temperature dependent; as the first warm days of spring accelerate crop growth, aphids ramp up just as fast – or faster. It may seem that the aphids came out of nowhere, but the truth is that it doesn’t take many undetected aphids to turn into a major infestation.

    Aphids can overwinter on weeds or plants, even in an unheated greenhouse. They can also be brought in on wind currents (similar to thrips), as well as purchased plant material. At the end of the growing season, be sure to remove all remaining plant debris and weeds; even small amounts of lingering plant material can harbor aphids for future re-invasion.

    Aphid feeding can cause distorted growth and lower leaf drop. Aphids also transmit many economically important plant viruses such as CMV (a significant disease of calibrachoa and petunia), and a majority of the viruses found in vegetable crops. In addition, the sugary excrement aphids leave behind, called honeydew, will grow unsightly black sooty mold. In fact, this sooty mold and the white ‘skins’ of exoskeletons shed as aphids mature are often the most obvious signs of an aphid infestation. 


    Aphid cast skins and black sooty mold


    The wide range of host plants and explosive reproductive capacity of aphids make them tough competitors for chemical and biological control programs. Scouting for early detection is very important, no matter which route you choose.

    For biological control, parasitic wasps should be released as the first crops are planted, long before aphid colonies are formed. On the other hand, even effective chemical control may leave anywhere from a few to a small percentage of aphids alive and well. The survivors can quickly build up a population.

    Biological controls can be effectively used to control aphids. Just as with a chemical program, a vigorous scouting program is required to be successful. The backbone of many biological aphid control programs are parasitoids, Aphidius colemani and Aphidius ervi

    Tan aphid mummies that have been parasitized by Aphidius wasps
    Generally speaking, A. colemani is used for the smaller species of aphids and A. ervi for the larger species. Griffin sells the parasitoids separately but also as a mixture since more than one species of aphids can be simultaneously active in a greenhouse, and identification by growers can be difficult. This mixture is sold under the trade names AphidiusForce CE and Aphiline ce.

    Aphidoletes aphidimyza is a midge with a voracious appetite for aphids that can be useful in combating hot spots of aphid activity. Green lacewing (Chrysoperla carnea) is a general predator which will consume aphids, as well as other prey.

    Biological controls come in various package types and sizes. Call GGSPro to find the best option for your needs. Griffin customers may also request our GGSPro Aphid Quick Sheet, which contains detailed tips for use and release methods for each biological control, along with rates and available package sizes.

    Aphid biological control organisms may be compatible with certain select pesticides, to help combat hot spots as needed. Please check with GGSPro to determine which products can be safely used with the predators and parasitoids you are using.

    With chemical controls, pesticide resistance is a significant concern. Rotate between at least three products from different modes of action to help reduce resistance pressure. Products with mode of action UN are at low risk for insect resistance; these may be used repetitively or to stretch rotations of traditional chemistry without the usual concerns. It’s vital that applicators read and follow the entire pesticide label. Products other than those mentioned may be safe and effective. Consult GGSPro for help in developing a responsible aphid control rotation.


    ProductMOACommentsItem Number
    Biologicals
    Ancora
    Botanigard 22WP
    Mycotrol WPO


    UN


    OMRI-listed or labeled for edible crops

    70-1166
    70-12521
    70-2420
    Soaps:
    Kopa
    M-Pede

    UN

    OMRI-listed

    70-1970
    75-10262
    Flagship 25WG
    Marathon 60 WP
    Safari 20SG
    TriStar 8.5 SL
    4A For use on some transplant-stage edible crops;
    check individual labels.
    70-1700
    70-23701
    70-29951
    70-85241
    Altus
    4D
    Labeled for some edible crops 70-1161
    Rycar
    Endeavor WDG
    9B Labeled for greenhouse use only 70-2900
    70-1660
    Kontos
    23
    Spray or drench effective.
    Not for use on geranium, cordyline, dracaena.
    70-19601
    Aria WDG
    29
    Stops pest feeding 70-3399
    Printable version

    Broad Mites: A Game of Hide and Seek

    Broad mites on Shasta daisy
    Curled leaves that lead to foliage looking hard and gnarled are symptoms that could indicate a broad-mite (Polyphagotarsonemus latus) infestation. Broad mites are typically found in the growing tips, causing stunting of that tender growing tissue. In severe cases, broad mites have also been found causing distortion on flowers and deformed fruit growth on certain edible crops.

    These mites are microscopic and difficult to locate even with 20X or higher magnification. Microscopic mites may be small but they can cause big problems for the many crops that host them including: ageratum, azalea, begonia, dahlia, gerbera daisy, ivy, bedding impatiens, lantana, marigold, New Guinea impatiens, peppers, snapdragon, torenia, verbena and zinnia.

    Broad mites on peppers
    Broad mite egg with geometric pattern

    Broad mites’ small size makes detection difficult and plant damage is often well underway before the source is discovered. Female broad mites are only 0.2 mm long and the males are even smaller. The females may pupate and wait in the soil until they find the appropriate host on which to feed.

    The broad mites also have distinctive eggs, which aid in their diagnosis. Their eggs are translucent and oval-shaped with a geometric pattern on the surface. These eggs are usually found on the undersides of leaves, but are sometimes found on the upper leaf surface as well.


    Broad mites on gerbera
    The detection dilemma is intensified by the fact that the mites are reclusive, often tucked away deep in the folded growing tip tissue. The nearly colorless broad mite injects a toxin as they feed, which contributes to the color change, cupping and even death of plant tissue. Since high soluble salts or environmental factors can cause similar symptoms, a positive identification is essential in making the correct treatment.



    Broad mites on ivy
    Translaminar systemic miticides are the preferred methods of control. Options include: Avid, Kontos, Pylon, Savate and Sirocco as foliar sprays and Kontos when applied as a soil drench. Akari and Sanmite are not translaminar systemics, but with good spray coverage they, too, may be successful. It’s advised that you always read pesticide labels and make sure to follow all label recommendations and restrictions. Products other than those mentioned here may also be safe and effective.




    ProductDescriptionItem Number
    Akari
    1 qt
    70-1160
    Avid
    8 oz
    70-1180
    Kontos
    250 mL
    70-19601
    Pylon
    1 pt
    70-2675
    Sanmite
    4 oz
    70-29201
    Savate
    8 oz
    70-2980
    Sirocco
    8 oz
    70-3017


    Printable version

    Shoreflies, Don't Bother Me! Prevention and Control Tips for Shoreflies and Fungus Gnats

    Fungus gnats and shoreflies are major pests among greenhouse crops, but they often don’t get the attention they deserve. These mini menaces wreak havoc on three different fronts: First, they creep consumers out by leaving their calling cards (fecal matter) on the foliage of otherwise beautiful plant material. Second, below the canopy, feeding larvae do direct harm to roots, stems and, occasionally, foliage (especially leaves in contact with growing media). The damage can be fatal, especially to young seedlings and cuttings in propagation. Third, adult fungus gnats and shoreflies are known to spread root and crown rot diseases in their travels. 
    Fungus gnat damage on dahlia leaf.


    In order to control fungus gnats and shoreflies, you must be able to properly identify them; some differences in chemical and biological control options need to be accounted for. Adult fungus gnats are dark, delicate-looking flies, similar in appearance to mosquitoes, with slender legs and long segmented antennae. Their wings are clear with a distinctive “Y” shaped vein. Fungus gnat larvae have a shiny black head and an elongated, whitish-to-clear, legless body. 
    Fungus gnat larvae with distinctive
    black head capsule.
    Photo credit: Bioline Agrisciences


    Shorefly adults more closely resemble miniature houseflies. Compared to fungus gnats, shoreflies are stronger fliers, with shorter legs and antennae. Shoreflies have five distinctive clear-to-white spots on their wings. Shorefly larvae are also clear to white, but lack a distinct head capsule. The pupal stage is dark brown with an interesting “fork” structure on one end[i]. While shorefly adults can spread plant pathogens, the larvae are not directly damaging to plants.


    Habitat Management

    Shorefly pupae. 
    Photo credit: Bioline Agrisciences
    Shorefly adult displaying spots on the wings.
    Habitat modification and sanitation are the first lines of defense against fungus gnats and shoreflies. Fungus gnats lay their eggs in cracks and crevices in the growing media. In greenhouses, this usually occurs on the surface of the soil but can happen in drain holes in the sides and bottom of pots, too. Constantly moist media, and the algae it encourages, make a suitable habitat for fungus gnat larvae. Shoreflies live in consistently damp areas with abundant algae. The larval stage feeds on algae and the pupal stage is semi-aquatic, partially submerged in water. Moisture management, including improved drainage and taking steps to limit algae, can pay dividends by creating a less favorable habitat for pest development.
    Power washing and approved cleaners such as Strip-it Pro can be used to remove organic matter from surfaces between crops. After a thorough cleaning, sanitation products such as: Greenshield II, Kleengrow, SaniDate 5.0 and Zerotol 2.0 can be used to finish the job and ensure a clean start.


    Control Options

    Chemical control of fungus gnats and shoreflies should target the larval stage because control of adults isn’t very effective with the available pesticides. The table below lists products recommended by GGSPro. All treatments are made to the soil.

    Product
    Package
    Active Ingredient
    MOA
    Fungus gnats
    Shoreflies
    Comments
    Item Number
    Adept
    1 lb
    Diflubenzuron
    15
    X
    X
    IGR, sprench, 21 days of control
    70-1150
    Citation
    1 lb
    Cyromazine
    17
    X
    X
    IGR, sprench, vegetable transplants
    70-13501
    Distance
    1 qt
    Pyriproxyfen
    7C
    X
    X
    IGR, sprench, soil surface spray, 21 days, Distance- fruiting vegetables
    70-1465
    Fulcrum
    1 qt
    Pyriproxyfen
    7C
    X
    X
    IGR, sprench, soil surface spray, 21 days, Distance- fruiting vegetables
    70-1710
    Gnatrol WDG
    16 lbs
    BT- israelensis
    11A
    X
    Make 3 applications 1 wk apart
    70-1716
    Pylon
    1 pt
    Chlorfenapyr
    13
    X
    Soil surface spray only, 7-14 days
    70-2675
    Safari
    3 lbs
    Dinotefuran
    4A
    X
    X
    Soil drench, vegetable transplants
    70-29951

    Biological control often begins with soil treatments of nematodes, which are highly successful in controlling the larval stages of fungus gnats and shoreflies. Choose Steinernema feltiae for fungus gnats and S. carpocapsae for shoreflies. Nematode treatments are generally effective for about 3 weeks and can be applied to all types of crops and most types of growing media. Following treatment, the number of adults will decline gradually, as the adults die off and fewer emerge from the soil to replace them.

    Dalotia coriaria, (aka Atheta or rove beetle), is a small beetle with a huge appetite for many soil-dwelling pests including fungus gnat and shorefly larvae, with thrips pupae control as an added bonus. Once established in a cool, moist location, they’ll often establish themselves in the crops. 
    Dalotia adult feeding on fungus gnat larvae.
    Photo credit: Bioline Agrisciences


    Stratiolaelaps scimitus (formerly known as Hypoaspis mites), is a tiny predator mite that patrols the soil surface and feeds on many of the same soil-dwelling pests as Dalotia.

    In greenhouses where pesticides are seldom used, the aptly named Hunter fly (Coenosia attenuate) will sometimes appear as a welcome ally. Hunter flies consume adult fungus gnats and shoreflies along with some other flying insects. They aren’t commercially available at this time, but they have been introducing themselves to commercial greenhouses in the northeastern U.S. 

    Hunter fly (Coenosia attenuata).
    Photo credit: Leanne Pundt, UConn


     Use yellow sticky cards to monitor for adult fungus gnats and shoreflies, and deploy the BCAs at the first sign of pest pressure. Certain compatible pesticides can be safely used in conjunction with biological control agents; contact GGSPro for assistance.

    Always read and follow all label directions. The label is the law! Products other than those mentioned may also be safe and effective. Some pesticides may be restricted-use or unregistered in certain states.



    Steinernema feltiae

    Product
    Manufacturer
    Description
    Item Number
    NEMAforce SF
    Beneficial Insectary
    50M - 1 tray x 50M
    30F50
    NEMAforce SF
    Beneficial Insectary
    250M -1 tray 250M
    30F250
    NEMAforce SF
    Beneficial Insectary
    1.25B -5 tray 250M
    30F5T
    Exhibitline Sf
    Bioline
    250M - 5 trays x 50M
    SB1011-02
    Exhibitline Sf
    Bioline
    1.25B - 5 trays x 250M
    SB1011-03
    Nemasys
    BASF
    250M - 5 trays x 50M
    70-2460
    Nemasys
    BASF
    1.25B - 5 trays X 250M
    70-2490
    Nemashield
    Bioworks
    100 M -1 cup
    70-6033
    Nemashield
    Bioworks
    500M -2 cups X 250 M
    70-6034
    Nemashield
    Bioworks
    2B- 8 cups X 250M
    70-6037
    Sentry
    NIC
    25M / sponge*
    70-7025
    Sentry
    NIC
    35M / sponge*
    70-7035
    Sentry
    NIC
    50M / sponge*
    70-7050
    * Order by Monday for following week ship


    [i] Shore Fly Biology and Control, J. Sanderson, Cornell - http://www.greenhouse.cornell.edu/pests/pdfs/insects/SF.pdf

    Printable version

    BCAs for Beginners: How to Get Started with Biological Controls

    The use of biological control agents (BCAs) to fight insect and mite pests continues to expand in the horticulture industry. Contributing factors include the desires to grow with eco-friendly techniques and to reduce chemical usage. Growers recognize the opportunity to appeal to customers with ‘natural’ products.

    As a chemical-free product, BCAs can add value to crops in several ways. First, many consumers are drawn to the notion of reduced risk from chemical exposure. Second, the knowledge gained by BCA usage over the years is making it easier for new users to succeed.
    Eretmocerus ememicus parasitic wasp

    If you’re considering biological controls, think of it as growing a new crop for the first time: Investing the time to understand the best cultural conditions of the BCA you want to use will very likely increase the initial level of success. Like plants, beneficial insects or mites work best in specific ranges of temperature, light and humidity. Most BCAs won’t establish easily in a population in your greenhouse, and will need to be released on a schedule in order to maintain control. Similar to growing a crop, the experience gained each year will lead to refinements and, hopefully, better results the next time around.

    Monitoring the BCA populations and the pest populations throughout the crop cycle is key. Doing so allows for adjustments to be made as needed in order to finish a high-quality crop. Scouting the plants for insect presence, counting and tracking insect trends on sticky cards and leaves, and recording the data definitely requires a commitment of time, energy and resources.

    GGSPro BCA compatibility chart. Click to enlarge.

    The scouting and monitoring process should measure the status of the battle in the canopy between BCAs and the pest target. This allows decisions to be made about quantities for continued releases of BCAs or whether a chemical intervention is called for. Yes, an insecticide or miticide may sometimes still be needed, but proper choice of a product will allow continued use of biological control with no or limited interruption. GGSPro has compiled compatibility data from suppliers and from researchers to assist with product selection. We assist our BCA customers with compatible pesticide choices by utilizing our searchable database.

    In reality, monitoring begins before the BCAs are released into the crop canopy. A quality assurance test should be done for each biological control after shipments are received and before each release to assess the vigor. Dr. Rose Buitenhuis, of Vineland Research and Innovation Centre in Lincoln, Ontario, has written the industry standard, Grower Guide: Quality Assurance of Biocontrol Products (available online), or ask GGSPro for guidance.

    Before diving into biological controls, plan ahead with a switch to softer chemistry or biological insecticides, such as Ancora, BotaniGard, SuffOil-X and M-Pede. Review pesticide application records from the previous four months, especially if broad-spectrum insecticides have been used. Note that drenches applied only to the soil may be completely compatible with the use of most beneficial insects, while a foliar spray of the same product may be harmful and require a waiting period before release.

    Speaking of drenches, nematodes are among the easiest entries into biological control, as they’re compatible with most foliar applications of chemicals and with many drench products. In the soil, the nematode Steinernema feltiae controls fungus gnat larvae and thrips pupae. Other species are available for control of Black Vine Weevil larvae and various grubs.

    Plan to start small with BCAs, as you would with any new crop. Try beneficials in a single house or just with an herb crop, for example. Plan for control of the pests normally expected in a certain crop, be it thrips in gerbera daisy or aphids on bellis or calibrachoa.

    Control of insect pests is most effective when biologicals are released before pest populations build. That is, before damage is readily visible, when pests are only detected through scouting activities, or when history leads to an expectation of a pest’s seasonal arrival. Many BCA species will feed on pollen or alternative insects in the absence of the target prey.

    Spider mite control is somewhat of an exception. In most crops, the predatory mite Phytoseiulus persimilis can overtake a moderate population of two-spotted spider mite and can clean up the crop. However, P. persimilis is only applied after spider mites have been detected, as it won’t feed on any other food source. In all other cases, the BCA is applied preventatively or proactively before pest populations build.

    If you’re considering biological control, plan ahead, plan to learn and plan to maintain realistic expectations. BCAs can be very effective, but they’re not a simple solution. Biocontrol is a dynamic process with many variables than cannot always be anticipated in advance. A commitment and dedication to monitoring populations is necessary to allow for early detection of expanding pest numbers. If needed, spray treatments can be used to reset the balance in favor of the biological control and provide a fresh start. A chemical ‘reset’ leads to analysis of timing and conditions in the biological strategy and becomes the experience that we build upon in the next cycle or the next crop.

    BCA products available from Griffin. Click to enlarge.

    Printable version

    Primula Particulars: How to Produce a Picture-Perfect Crop

    Primula has a delightful way of ushering in the spring season with an extraordinary blast of color and fragrance. This cool-weather crop has gone through extensive breeding over the years, resulting in a wide array of intense colors. The dull grays and browns of winter can be replaced with clusters of vivid flowers over a compact rosette of green foliage. Primula is a crop that just makes people happy.

    Primula is typically grown one plant per 4” to 4½" pot, and requires a well-drained soilless mix with an ideal pH of 5.3 to 5.8. Primula is a long-term crop from seed. Growing from plugs or cell pack liners saves time and sidesteps germination problems during the summer heat.


    Primula Crop Timing and Temperature Requirements

    When using the following tables, bear in mind that a primula crop flowers over a fairly long period of time. Primula are classified as early, mid-season or late. The crop times outlined below will be affected by your growing conditions.


    Plug Size
    288s

    128s

    70s
    Early Season12-14 weeks10-12 weeks8-10 weeks
    Mid Season14-16 weeks12-14 weeks10-12 weeks
    Late Season16-18 weeks14-16 weeks12-14 weeks



    From Plug

    Day

    Night

    Planting to 5 Weeks

    70°F or less (Encourages adequate foliage to develop before bud set.)

    60-65°F

    Early Season
    5 Weeks to Visible Bud

    55-60°F

    50°F

    Early Season

    45-60°F (Temperature depends on forcing requirements.)

    50°F (If there is a need to force bloom 60-62°)

    Fertilizer

    Primula leaf curl caused by calcium deficiency
    Primula fertilizer requirements change during the crop cycle. Higher ppm are used during the warm period (first 4-5 weeks) and then reduced during the cool period. Fertilizers should provide most of the nitrogen in the nitrate form and should be acid-forming to help hold pH down (5.3-5.8). A standard fertilizer program that works well for primula is 20-10-20 rotated with 15-0-15. The exact rotation is dictated by the water quality.

    Primula requires ample amounts of iron and magnesium to maintain rich green foliage. If media or tissue analyses indicate a deficiency, prompt treatment is needed. Iron can be provided by applications of iron chelate (Sprint 138 or 330) as a drench at 4 oz/100 gal. Be sure to rinse the excess off of the foliage to avoid any phytotoxicity.

    Magnesium can be supplied as Epsom salts by applying 8 oz/100 gal as a pulse treatment or 2 oz/100 gal on a constant feed basis. Epsom salts cannot be tank-mixed with calcium fertilizers, such as the 15-0-15.

    The short, overcast days of winter will make it harder for the plants to take up calcium, as their transpiration rates are much lower in these conditions. Curling leaves are a symptom of calcium deficiency on primula. Additional calcium can be applied with foliar sprays of calcium chloride dihydrate at 0.5 oz/3 gal of water (1 lb/100 gal), along with 0.25 tsp/gal (4 oz/100 gal) of CapSil as a spreading agent.


    Crop StageFertilizer Rates
    Planting to 5 Weeks200 ppm CLF
    5 Weeks to First Color150 ppm CLF
    First Color to SaleClear water

    Plant Growth Regulators

    Primula growth is controlled with cool temperatures; PGRs are seldom needed. If necessary, the following growth regulators are effective:
    Sprays

    • B-Nine 2500 ppm (2 Tbls/gal)
    • Bonzi at 10 ppm (2 tsp/gal)
    Drench

    • Bonzi 0.5-1 ppm (1.66-3.33 ozs/gal thru the injector at 1:100)
    *Do not use Florel on primula

    Melting Down or Scorching

    Tip scorch on primula
    The first step in preventing primula foliage from melting down or scorching is to check crown and root zones to rule out diseases such as Pythium, Phytophthora or Rhizoctonia. Keeping soil too wet during low light levels can lead to root rot.

    If we’re able to rule out diseases, we then need to dig deeper. Primula is a cool crop that’s grown during the time of year when we experience our shortest days and lowest light levels – December through February.

    Physiological disorders sometimes are behind the symptoms. Daylength and light intensity increase toward the end of the primula crop cycle; this created water stress when combined with cold soil temperatures that slow root activity. Bright days of late winter can create enough of a water deficit that the margins of the leaves scorch. This is particularly true on the first sunny day after a spell of cloudy weather! Consider syringing overhead a few times during the brightest part of the day to reduce water stress, allowing enough time for foliage to dry before nightfall.


    Diseases and Insects

     
    Botrytis on primula Thrips damage on primula flowers
    Botrytis is the most common disease found in primula. This crop requires cool conditions and high humidity to produce good quality plants, both of which favor the development of Botrytis. Good sanitation, watering early in the day and good air movement all help control and prevent disease.

    Even with the best cultural controls, fungicides sprays are often still necessary. Products that have shown good efficacy on Botrytis either as a preventative or curative spray include Affirm, Astun, Botrystop, Cease, Mural, Pageant, Palladium and Triathlon BA.


    Insects that target primula are aphid, fungus gnat, shorefly, thrips and caterpillars. Consult the GGSPro team for detailed pest control options and rates.



    ProductDescriptionItem Number
    Jack's WSF 15-0-15
    25 lb
    33626
    Jack's WSF 20-10-20
    25 lb
    33615
    Affirm
    .5 lb
    71-1129
    Astun
    1 qt
    71-1190
    Botrystop
    12 lb
    71-1260
    Calcium chloride dihydrate
    1 lb
    35315
    CapSil
    1 gal
    74-1541
    Cease
    1 gal
    71-13301
    Epsom salts
    50 lb
    14MGSUL
    Mural
    1 lb
    71-1690
    Pageant
    1 lb
    71-26801
    Palladium
    2 lb
    71-2685
    Sprint 138
    5 lb
    67-70371
    Sprint 330
    5 lb
    67-70361
    Triathlon BA
    1 gal
    71-3040
    Printable version

    Mind Those Mites: Scouting and Control Tips for Poinsettia

    Most growers would agree that summer conditions favor spider mites. Warm temperatures shorten life cycles, causing explosive mite populations. As weather shifts from hot and dry to cooler conditions with long nights during poinsettia season, mite pressure is reduced.

    Lewis mite damage on poinsettia
    Lewis mites and, occasionally, spider mites can be problematic for poinsettias. Growers are often challenged to tell the difference between the two species. Both prefer to feed on the undersides of leaves, laying eggs closest to the midrib. Both mites will produce webbing, though Lewis mites only do this when the infestation is heavy.

    Mites won’t be found on sticky cards, so scouting for early detection of eggs or mites is especially crucial. Concentrate scouting in areas of the greenhouse where air movement is highest. This is where you’ll find the lower humidity that mites prefer.

    Mature foliage may begin to reveal symptoms that mimic nutritional deficiencies. Observe foliage for faint light green to yellow speckling. Mites can be easily identified with the use of a hand lens while examining the undersides of leaves. A useful tool is the beating tray to tap foliage for mite presence. Against white paper, mites may appear like moving speckles of black pepper. The chart below provides key characteristics of both mite species.


    Life stages of the two-spotted spider mite and Lewis mite.
    Photos credit: Dr. Surendra Dara, University of California



    
    Two-Spotted Spider Mite Lewis Mite
    Host range Multiple hosts. Pest of field crops and greenhouse plants. Multiple hosts. Mainly greenhouse pest. AKA poinsettia spider mite.
    Male Wedge-shaped, 0.3 mm Wedge-shaped, mustard-colored, 0.25 mm
    Female Oval, 0.4-0.5 mm. Single dark spot on either side of the body Oval, 0.36 mm. Multiple small spots
    Life stages Egg, larva, protonymph, deutonymph and adult Egg, larva, protonymph, deutonymph and adult, though males have only one nymphal stage
    Egg Round, clear initially and turns whitish as it matures Round, pale-greenish and turns light orange with maturity
    Egg laying About 100 eggs in 10 days About 60-90 eggs in a month
    Life cycle 5-20 days depending on temperature 12-14 days at 70°F
    Diapause Ceases reproduction during cold winters Continuously reproduces without diapause
    Damage Feeds undersurface of leaves. Causes yellow mottling, scarring, bronzing and leaf fall-off Similar, in general, but needs to be determined on strawberries
    Webbing Prominent At high infestation levels
    Predatory mites Phytoseiulus persimilis, Neoseiulus californicus, N. fallacis, Amblyseius andersoni, etc. N. californicus, N. fallacis, A. andersoni, etc.
    Chart credit: Dr. Surendra Dara, University of California

    Unless growers are certain which mite is present, GGSPro recommends miticides that control both species, making two applications one week apart.

    CapSil is a high-quality surfactant that improves spray coverage. During poinsettia bract formation, CapSil rates are reduced to 4 oz per 100 gal. Not more than one application of CapSil per week is made to ensure plant safety.

    Pesticide information in this bulletin is believed to be correct but it is the responsibility of the applicator to read and follow all label directions. Labels do change without notice. Pesticides other than those listed may also be safe, legal and effective.


    Miticide
    Size
    MOASpider mitesLewis MitesItem Number
    Akari 5SC
    1 qt
    21A
    X
    X
    70-1160
    Avid 0.15 EC
    Minx 2
    1 qt
    6
    X
    X
    70-1185
    70-2398
    Beethoven TR
    12-2 oz cans
    10B
    X
    X
    70-1234
    Floramite SC
    1 qt
    20
    X
    some
    70-1653
    Kontos*
    250 ml (8.45 oz)
    23
    X
    70-19601
    Sanmite 75 WSP
    4-1 oz packages
    21A
    X
    70-29201
    Savate/Judo
    8 oz
    23
    X
    X
    70-2980
    Shuttle O
    1 pt
    20B
    X
    X
    70-30151
    Sirocco SC
    8 oz
    6/20
    X
    X
    70-3017
    Sultan
    16 oz
    25
    X
    70-3045
    Tetrasan 5 WDG
    1 lb
    10B
    X
    X
    70-3130
    *Drench only, applied early in crop
    Note: Pylon cannot be used on poinsettia.

    Under Pressure: How to Defend Against Fall Pansy Diseases

    Few crops can compete with the performance of pansies and violas during this time of year! For many regions, fall pansies are a landscape staple, providing impressive color through the autumn and winter months. In northern regions, pansies provide fresh fall color and can overwinter to provide an early burst of color in the spring. Breeders have ensured there’s a lot to enjoy: a myriad of colors, flower sizes and new plant habits. From the grower perspective, pansies also provide a welcome profit center that’s independent of spring.

    Even with improved genetics, pansies are still a cool-season crop. Fall-flowering crops are typically started when the weather is quite warm, even hot, and therein lies the challenge from a disease-prevention standpoint. Two diseases of the root and crown earn mention for being particularly challenging for fall pansy production: Thielaviopsis and Phytophthora.

    Thielaviopsis causing uneven growth in flats of pansies
    Thielaviopsis, also known as Black Root Rot, is a devigorating disease of pansies that’s inhibited to some extent at a soil pH below 5.8. Warning signs include roots that darken and are reluctant to grow out of the original plug. Infestations are often random in appearance with stunted pansies right alongside plants that are thriving. Unless you have a microscope and can identify Thielaviopsis spores in the roots, suspicious plants should be sent to a plant diagnostic lab for a positive identification.

    Plants infected with Thielaviopsis cannot be salvaged, meaning fungicide treatments are used to protect adjacent healthy plants. Given the susceptibility of pansies and the environmental stresses early in production, GGSPro recommends a preventative drench soon after transplanting. The products we recommend for Thielaviopsis also control Rhizoctonia.

    Phytophthora is seldom found in winter/spring-grown pansies but can cause substantial losses in late summer and early fall. Warm temperatures and abundant splashing water favor this fast-moving disease. The zoospores (swimming stage) of Phytophthora can readily move about and enter healthy plants via the drain holes in pots and flats. For this reason, growing the crop up off the ground is very desirable. Benches are ideal; however, inverted flats or 1” PVC pipes under the flats will serve the purpose.

    Effective fungicides may be applied to address Phytophthora, but to be successful it’s important to reduce the risk for spread. Learning to identify the early symptoms as well as the conditions that make disease expression more likely is also key. Watch for sudden stem constriction and collapse at the crown. Rootshield Plus is a fungal-based preventative fungicide that includes Phytophthora prevention due to the addition of a second strain of Trichoderma to the original formulation. It’s also labeled for prevention of Thielaviopsis. Chemical control options appear in the table below.

    Pansy infected with Anthracnose
    Foliar diseases become more prevalent as the crop progresses and the weather cools. Anthracnose (Colletotrichum), Botrytis and Cercospora are among the troublemakers.Anthracnose symptoms on pansies generally appear as large necrotic and chlorotic lesions that are somewhat irregularly shaped. Often, faint concentric rings can be detected within the necrotic tissue. Botrytis can be especially problematic as early blooms begin to senesce and “melt,” sometimes involving adjacent foliage. Cercospora often manifests itself with dark purple spots, some of which have tan centers, giving rise to the “fish eye” description.

    Much more information on these and other diseases that affect pansies is available through GGSPro and the GGSPro 4th Edition Reference Guide, which includes cultural and chemical controls, as well as helpful diagnostic pictures. The tables below also contain fungicide suggestions.


    Products for Root and Crown Diseases

    Apply as soil drenches except as noted. The Affirm label forbids chemigation; bulk tank application is needed.


    Disease FungicideMode
    Of
    Action
    (MOA)
    CommentsItem number
    ThielaviopsisAffirm
    19
    Chemigation label expected fall 201771-1129
    Cleary’s 3336 EG
    1
    Max label rate, re-apply in 3 weeks71-2550
    Cleary’s 3336 F
    1
    Max label rate, re-apply in 3 weeks71-2575
    Emblem
    12
    Name will change to Spirato GHN71-1570
    Medallion
    12
    2 oz per 100 gal rate71-16502
    OHP 6672 F
    1
    Max label rate, re-apply in 3 weeks71-2670
    OHP 6672 WSP
    1
    Max label rate, re-apply in 3 weeks71-2672
    Orkestra Intrinsic
    7 & 11
    New product, trial for plant safety71-2200
    Rootshield Plus G
    UN
    Pre-incorporation 71-27911
    Rootshield Plus WP
    UN
    Best applied at time of transplant71-27951
    PhytophthoraAreca
    33
    Foliar spray, avoid open bloom71-1180
    Aliette
    33
    Foliar spray, avoid open bloom71-11352
    Alude
    33
    Foliar spray or drench71-27601
    Banrot
    1 & 14
    Soil drench, use max label rate71-1210
    Fosphite
    33
    Foliar spray or drench71-1520
    Heritage
    11
    Foliar spray or drench, preventative71-1400
    Micora
    40
    Foliar spray or drench71-1655
    Orkestra Intrinsic
    7 & 11
    New product, trial for plant safety71-2200
    Orvego
    40 & 45
    Foliar spray or drench71-2300
    Rootshield Plus G
    UN
    Pre-incorporation 71-27911
    Rootshield Plus WP
    UN
    Best applied at time of transplant71-27951
    Segovis
    U15
    Foliar spray or drench71-3100
    Segway
    21
    Foliar spray or drench71-31101
    Stature SC
    40
    Foliar spray or drench71-14652
    Subdue MAXX
    4
    Some resistance reported71-2978

    Products for Common Foliar Diseases of Pansies

    FungicideMOAAnthracnoseBotrytisCercosporaItem Number
    Affirm
    19
    x
    x
    71-1129
    BotryStop
    NC
    x
    71-1260
    Camelot O
    M1
    x
    x
    70-21202
    Cease
    44
    x
    x
    x
    71-13301
    Compass
    11
    x
    x
    71-1355
    Daconil Ultrex
    M5
    x
    x
    x
    71-1420
    Daconil Weatherstik
    M5
    x
    x
    x
    3117025
    Eagle
    3
    x
    x
    71-1435
    Emblem / Spirato GHN
    12
    x
    x
    x
    71-1570
    Heritage
    11
    x
    x
    71-1400
    Medallion
    12
    x
    x
    x
    71-16502
    Nordox
    M1
    x
    x
    71-1700
    Mural
    7 & 11
    x
    x
    x
    71-1690
    Orkestra Intrinsic
    7 & 11
    x
    x
    x
    71-2200
    Palladium
    9 & 12
    x
    x
    x
    71-2685
    Pageant Intrinsic
    7 & 11
    x
    x
    x
    71-26801
    Phyton 35
    M1
    x
    x
    71-2737
    Protect DF
    M3
    x
    x
    x
    71-2748
    Strike Plus / Trigo
    3 & 11
    x
    x
    x
    70-3035
    Triathlon BA
    44
    x
    x
    x
    71-3040
    Zerotol 2.0
    NC
    x
    x
    71-35501

    Read and follow all label directions. The label is the law! Products other than those mentioned may also be safe and effective. Some pesticides may be restricted-use or unregistered in certain states.

    When Less is More: Using Bonzi Micro-Drenches on Poinsettia

    Controlling poinsettia height throughout the growing cycle is key to avoiding problems at the time of sale. Research has shown that most plant stretch occurs in the first three hours of the day, beginning at first light. One method that greatly reduces stretch is to drop the temperature during this time frame, by 5o F below the night temperature. Discontinue this technique when the cyathia become visible.

    When it comes to maximizing bract expansion, poinsettias benefit from as little plant growth regulators (PGRs) as possible. The less applied, the better. Foliar sprays of PGR are more likely to reduce bract size than drenching. Bonzi drenches can be utilized to encourage uniform poinsettias of ideal height without significant reductions in bract size.

    Dramm CD-2 Chemdose
    Bonzi “micro-drenches” were developed and named by Dr. Jim Barrett from the University of Florida. This technique utilizes drenches of low rates of Bonzi, usually in the range of 1/10th to 1/8th ppm that can be made as often as weekly if required throughout the production cycle. (After October 25, higher rates can be used if needed with a reduced impact on bract size. Read on for details.) Bonzi micro-drenches may be applied through an injector or Dramm Chemdose. The CD-2 Chemdose from Dramm precisely doses PGRs or soil-applied pesticides, and is ideally suited for applying micro-drenches. Doses as low as 2.5 mL can be delivered accurately. The CD-2 connects to your injector or hydraulic sprayer at pressures lower than 100 psi. Weighing less than 10 lbs., the CD-2 can be worn on the chest or mounted on a small cart.

    Graphical tracking is very helpful in managing plant height among varieties of varying vigor. Such tracking ensures that data-based decision making is employed. Graphical tracking is available at http://www.ecke.com/OnTarget/CreateAccount.aspx


    Bonzi "Micro-Drench" Strategy



    Medium-Vigor Verieties High-Vigor Varieties
    South 1/10th - 1/7th ppm 1/10th - 1/5th ppm
    North 1/10th ppm 1/8th ppm


    Bonzi "Micro-Drench" Rates



    ppm tsp/100 gal oz/100 gal Ml/100 gal
    1/5th 4 0.64 20
    1/7th ~3 0.46 14.3
    1/8th ~2.5 0.4 12.5
    1/10th 2 0.32 10


    Bonzi PPM Drench Volumes



    Pots Baskets Other
    Container Size oz per pot Container Size oz per pot Container Size oz per pot
    4" 2 8" 10 14" coco 37
    4.5" 2.5 10" 15 16" coco 46
    5" 3 12" 28 10" Dillen color 25
    6", 6.5", or 7" azalea 4 14" 56 12" Dillen color 43
    7.5" azalea 9 15" Dillen color 58
    8" azalea 10
    8.5" azalea 13
    10" azalea 25
    12" 43


    Starting after October 25, higher drench rates (0.25-1.0 ppm) can be used to provide stronger hold if needed with a slight reduction in bract size. Very vigorous varieties, for example, would apply a Bonzi drench at a rate of 1.0 ppm. Consult with GGSPro or your Griffin sales representative for varietal response information to determine if a Bonzi drench rate would be beneficial or necessary to avoid late-season stretch.

    Product Description Item Number
    Bonzi 1 qt 70-1260
    Bonzi 2.5 gal 70-1270
    Paclo Pro 1 gal 73-1830
    Dramm CD-2 ChemdosePrecision flow meter, battery operated41-1196

    The Way to a Plant’s Heart is Through its Roots: Building Strong Plants with Organic and Natural Nutrition Options

    Organic, natural, all-natural and chemical-free are all terms deemed to add value to our food and flower crops. Even if you never intend to grow organically or chemical-free, there is an undeniable trend toward more natural products, sustainable methods and limited chemical exposure.

    Growers have been struck with a need for more choices in plant nutrition and pest control to produce chemical-free crops economically and without losses. Insect- and disease-control options can be very limited for specific crops, most notably, herbal crops. Nutrition and building a strong plant, of course, are the first lines of defense against pests and disease.

    Growers have been struck with a need for more choices in plant nutrition and pest control to produce chemical-free crops economically and without losses. Nutrition and building a strong plant, of course, are the first lines of defense against pests and disease.

    At Griffin, we’ve expanded our selections of organic (OMRI-listed or WSDA) and organic-based nutritional products and supplements to fill this need. Nature’s Source 10-4-5 Nursery & Landscape Special Plant Food is an organic-based product, but not organic certified. Like Nature’s Source OMRI-listed 3-1-1, the Nursery and Landscape formulation is a liquid product derived from an oilseed extract. However, the Nursery and Landscape product contains higher levels of the essential micronutrients. Organic granular fertilizers with slow-release profiles are available in EcoVita 7-5-10 (100-day) by Verdanta and in Sustane’s 8-4-4 All Natural (45-day). Both are OMRI-listed.

    Vegetables and other crops with high potassium demand can be easily supplemented with Verdanta’s granular K-Vita (OMRI), Verdanta’s liquid PL-2 (OMRI) or JH Biotech’s Biomin Potassium liquid non-organic formulation. Additionally, nitrogen content can be easily boosted as needed with the new Biomin N, 5% nitrogen in a liquid mix of amino acids derived from hydrolyzed plant protein (OMRI-listed), without increasing phosphate or potassium.

    Organic, liquid formulations of micronutrients are now available. Biomin Booster 126 is a mix of micros, providing copper, iron, magnesium, manganese, boron and zinc. Biomin Calcium provides 5% calcium in a formulation that aides in calcium uptake through foliage or roots. Biomin Magnesium contains 3% chelated magnesium and can be applied as a drench or to the foliage. Other elements are also available.

    Beyond the nutrition basics, we offer several products designed to provide artificial growing media with more of the components found in natural soils. Silica has been shown to reduce pest and disease infestation of a number of crops. SiTKO 0-7-17 (5% silica) or Sil-Guard 0-2-5 (7% silica), by Growth Products, can be used to add silica to growing media or to mineral soils. Silica has been shown to increase the strength of cell walls, making at least some plants resistant to invasion by pathogens or insects. Drought resistance/recovery and reduced shock during propagation and transplanting are additional benefits. Silica also competes with sodium, and can mitigate damage due to high salt content. Contact GGSPro to determine if a silica supplement may be appropriate for your production.

    Beyond the nutrition basics, we offer several products designed to provide artificial growing media with more of the components found in natural soils.

    Some of the most complex components of natural soils, humic and fulvic acids, are now available in a jug from JH Biotech, Inc. These complex materials originate from the breakdown of organic matter. They’re known benefactors of plant growth, increasing the cation exchange of soils and facilitating the uptake of micronutrient metals. Humax is 12% humic acid and is OMRI-listed; Fulmax is WSDA organic. Even natural mineral soils can benefit from replenishing or boosting the silicate, humate and fulvate content in poor or depleted soils.

    Essential Organic 1-0-1 combines 7% humic acid with a long list of other natural ingredients, including cellulose, lignin, amino acids, sugars, plant hormones and micronutrients calcium, magnesium, sulfur and iron, all in a non-settling, non-clogging formulation. The natural rooting hormones in Essentials Organic promote rooting in propagation and in production.

    No matter which crops you grow, from organic produce to perennials, these products may have a place in your production and provide your plants with everything they need to grow strong.

    ProductCommentsDescriptionItem Number
    Nature’s Source 10-4-5 Nursery & Landscape SpecialOrganic-based4.7 gal67-0086
    Nature's Source 3-1-1OMRI4.7 gal67-0065
    Verdanta EcoVita 7-5-10OMRI, 100-day40 lbs67-9215
    Sustane 8-4-4 All-NaturalOMRI, 45-day50 lbs67-30570
    Verdanta K-Vita 2-0-20OMRI40 lbs67-9205
    Verdanta's PL-2 2-0-6OMRI1 gal67-9220
    Biomin Potassium1 gal16-03481
    Biomin NOMRI1 gal16-03421
    Biomin Booster 126OMRI, WSDA1 gal16-03081
    Biomin CalciumOMRI, WSDA1 gal16-03011
    Biomin MagnesiumOMRI, WSDA1 gal16-03041
    SiTKO 0-7-17Contains silica, phosphate, salicylic acid2.5 gal16GP30053
    Sil-Guard 0-2-5Contains silica and phosphite2.5 gal16GP501821
    HumaxOMRI, WSDA1 gal16-01111
    FulmaxWSDA1 gal16-01181
    Essential Organic 1-0-1OMRI1 qt166002GR

    Beetle Mania: Let's Start a Revolution (in Japanese Beetle Control)

    Did you know that, according to the Entomological Society of America, there are more than 30 million insect species in the world? At any one time, it’s been estimated that you could count 10 quintillion insects present on the earth!
    The United States alone is home to more than 23,000 species of beetles. GGSPro has helped growers deal with infestations of ambrosia, Asiatic, box elder, cucumber, Colorado potato, flea, lily leaf, longhorn, pine bark, potato, tortoise and turpentine beetles, to name a few. One beetle generates more inquiries than any other: the Japanese beetle.
    GGSPro has helped growers deal with many kinds of beetle infestation. One beetle generates more inquiries than any other: the Japanese beetle.
    Adult Japanese beetles on rose
    Adult Japanese beetles emerge from the soil and begin feeding in June. They are ½” long and have a hard metallic green shell with copper colored wings. The small white tuffs of hair that stick out from their abdomen help to distinguish Japanese beetles from other species.
    The adults have a short life span, roughly 40 days. Female Japanese beetles feed, mate and lay eggs, repeating this process every 24-48 hours. At each egg laying, the female beetles deposit one to five eggs 2-4” deep in soil.
    Japanese beetle larvae emerge in early August and feed on plant roots. They are whitish gray C-shaped grubs ¾” long with six legs. Japanese beetle grubs can be identified by the V-shaped pattern of hairs on their behinds.
    Japanese beetle grub
    Actively feeding Japanese beetles secrete a pheromone which attracts other adult beetles. This enables them to attack plants in groups, causing severe damage.
    The following products are insecticides that are labeled for Japanese beetles and are available from Griffin. Most of these products represent some risk to bees. Refer to the bee safety codes and explanations below to make the best choices. 
    Product Item # Comments
    Acephate 97UP 70-1105 Residual control about 7 days.
    RUP: NY
    Avalon Golf & Nursery
    Insecticide
    70-1210 Do not use in Nassau or Suffolk County, NY
    Coretect 70-1380 Systemic product must apply prior to adult emergence.
    RUP: CT, MD, NY
    Chlorpyrifos SPC 4 70-14852 Restricted-use pesticide
    Decathlon 70-14201 Quick knockdown, short residual control
    RUP: VT, NY
    Discus N/G
    Discus L
    70-1409
    70-14094
    RUP: CT, MD, NY
    Duraguard 70-21261 RUP
    Flagship WG 70-1700 RUP: NY, MA
    Mainspring 70-2331 RUP: NY
    Marathon II 70-23711 RUP: CT, MD, NY
    Marathon WSP 70-23701 RUP: CT, MD, NY
    Mallet 2F T & O 70-2340 RUP: CT, MD, NY
    Mantra 60% WSP 70-2350 RUO: CT, MD, NY
    Menace GC 7.9% 70-2389 RUP
    Pyganic 5.0 Specialty 70-2687 RUP
    Safari 20 SG 70-2995 RUP: CT, MA, MD, NY
    Sevin SL 70-3002 Quick knockdown, short residual control
    Talstar Pro 70-34121 Quick knockdown, short residual control
    RUP: CT, MA, NY, VT
    TriStar 30 SL 70-85221 Considered nontoxic to bees after 3 hours
    RUP: MD, NY
    Toxicity Key
    Highly Toxic
    EPA Describe as highly
    toxic or very highly toxic to
    bees
    Low Toxicity
    EPA describe as a potential pathogen
    or with low toxicity to bees
    Toxic
    EPA describes as toxic to
    bees
    Special Case
    Special use notes per label; contact
    GGSPro for more information

    Exposure Key

    1. Toxicity risk through both direct exposure and residual exposure - avoid treatment when bees are visiting the treatment area.
      Visiting the treatment area refers to bees that may visit the plants after treatment. Bees are protected when bees are absent from the treetment area bot hduring and following treatment. Avoid use of these products when crops and/or weeds are in bloom.
    2. Toxicity risk through residual exposure only - avoid treatment when bees rae visiting the treatment area.
      Visiting the treatment area refers to bees that may visit the plants after treatment. Bees are protected when bees are absent from the area following treatment. Avoid use of these products when crops and/or weeds are in bloom.
    3. Toxicity risk through direct exposure only - avoid treatment when bees are actively visiting or actively foraging in the treatment area
      Actively visiting the treatment area referse to bees you see on the plants and pertains to the products that do not show residual effect. Bees are protected when bees are absent during treatment.

    Garden Mums and Florel: New Research to Prevent Premature Budding

    Ethephon is the active ingredient in several widely used plant growth regulators (PGRs), including Florel, Collate and Verve. Research conducted by Peter Konjoian in the 1980s laid the foundation for other researchers and growers to learn how to harness the power of ethephon. Some of Florel’s attributes include increasing lateral branching, improving plant architecture, maintaining plants in a vegetative state and reducing internode elongation.

    Mystic Mums, photo courtesy of Dummen Orange
    Konjoian also documented the “dark side” of ethephon: It’s a stress enhancer, leading to the recommendation that applications only be made to actively growing plants that are free from water, transplant or other stresses in order to avoid adverse plant reactions.

    For many years, GGSPro has recommended Florel applications for garden mum crops. The benefits for this important crop include reducing the risk of pre-mature budding, optimized branching even under adverse conditions and the ability to influence the bloom date. We often refer to Florel applications as “cheap insurance” for garden mum growers.

    Chrysanthemum crown buds

    Our recommendation, historically, has been to apply a foliar spray of Florel at 500 ppm as soon as the rooted cuttings arrive and then make a second application 2 weeks later. This program has served growers very well, but the ability to overcome pre-mature budding under cool early-season conditions has been variable. In some cases, it worked like a charm; in other cases, it didn’t fully succeed.

    Research shared in fall 2016 at the FRA Research Meetings by Jim Faust answers our questions about the lack of consistent success we saw in attempting to stop pre-mature budding. Thanks go to Jim Faust and Audrey Lecordier from Clemson University for allowing us to summarize their important garden mum research in this bulletin.

    Faust and Lecordier set out to determine treatments needed to prevent pre-mature budding of natural-season garden mums produced under cool summer conditions. They demonstrated that extending the photoperiod, even up to 16.5 hours, did not stop pre-mature budding with a simulated cool summer temperature regime of 55° nights and 65° days.

    The same held true for night interruption treatments. Next, they made 1, 2 or 3 Florel treatments beginning after 3 weeks of simulated cool temperatures. Concentrations ranged from 500-1000 ppm. They made several important observations that can significantly impact garden mum production:

    • Flower initiation may occur earlier than previously thought, leading to a recommendation to apply 500 ppm Florel in the rooting phase. This is deemed sufficient to keep the mums in a vegetative state coming out of propagation.
    • Three weekly applications of 750 ppm of Florel can re-set the flower clock during periods of cool summer weather that might otherwise lead to pre-mature budding.
    • Natural-season garden mum crops can be timed even with cool summer conditions by making weekly applications of 750 ppm Florel during the vegetative phase. Make the last Florel application one week ahead of the response time weeks to ship in the first color stage. As an example: For a variety with a 6-week response time, make the last Florel application 7 weeks before the desired first-color date. (While a useful tool, consider the timing approximate and subject to factors such as heat delay. Keep good records and refine your approach with experience.
    • Garden mums receiving 3 weekly Florel applications had significantly more buds and blooms per stem when compared to plants receiving 0, 1 or 2 Florel treatments. In this experiment, the control plants averaged 35 buds and blooms per stem while the mums receiving three applications of Florel at 750 ppm averaged 54 buds and blooms per stem.

    Florel has the effect of reducing internode elongation in many treated plants, so it’s reasonable to expect that garden mums receiving the recommended amount of Florel treatments might finish shorter than untreated plants. In this experiment, however, the plants receiving three 750 ppm Florel applications were slightly taller than the control plants. This is probably due to the fact that they stayed vegetative longer than the control plants, outweighing the internode elongation reduction effects of Florel.

    Special instructions regarding the use of Florel

    Foliar spray applications of Florel should be applied evenly across all plant surfaces to the point of drip. It does not translocate from treated to untreated foliage. GGSPro does not recommend the use of surfactants with Florel.

    Highly alkaline water may need to be treated in order for Florel to be effective. When Florel is added to the spray tank it must be able to drop the pH of the spray solution to 5.0 or lower to work properly. Distilled or acidified water may be needed in some cases. Indicate 5 can also be used to adjust the final pH of the spray solution. Do not apply Florel to plants under water stress. Slower drying conditions will maximize the effectiveness of Florel applications.

    Typical Florel Program for Garden Mums


    Floral ppm
    During propagation500
    Upon arrival rooted cuttings500
    Two weeks later500


    Florel Program For Garden Mums in Conditions with Medium-to-High Risk of Premature Budding


    Florel ppm
    During propagation500
    Risk identified750
    One week later750
    One week later750


    Florel rates: 500 ppm = 1.6 oz per gal, 750 ppm = 2.4 oz per gal

    Note: Florel treatments made after July 5th will likely delay the natural-season bloom date.
    Call GGSPro for questions regarding the use of Florel or Indicate 5.


    ProductsDescriptionItem Number
    Florel 3.9%1 qt608-395
    Florel 3.9%1 gal55-100161
    Indicate 51 gal31705







    A New Option in Pest Control: A First Look at Altus Insecticide

    Altus is a new insecticide product from Bayer, offering some unique benefits to growers of ornamentals and edibles. Although more data is needed to better understand the impact and performance of Altus over time, early indicators suggest it will be a useful tool in the growers’ arsenal.

    Aphids on calibrachoa
    Altus is a new soluble concentrate (SC) formulation of a broad-spectrum insecticide with a unique mode of action (MOA 4D). It’s labeled for use in greenhouses, field and container nurseries, shadehouses, interiorscapes and landscapes. Altus can be applied as a foliar spray for aphids, leafhoppers, plant bugs and whiteflies. Suppression of scale and Western flower thrips can also be expected.

    One of the unique features is the edible crop uses on the label. Altus is labeled for use on a lengthy list of vegetable transplants. In addition, cucumbers, lettuce, peppers and tomatoes can be treated when grown to harvest with a 1-3 day pre-harvest interval (PHI), depending on the crop.

    Altus is effective against all life stages, including eggs in some cases. It’s rain-fast in one hour, and has demonstrated good safety with bees and many BCAs (more data is still needed regarding BCA safety). Altus will not require an EPA bee safety box on the label. Growers that have chosen not to use neonicotinoid insecticides can effectively substitute Altus and control most of the same pests without the associated bee hazards.

    Four-lined plant bug damage on coleus
    Plant and bloom safety has been excellent. Altus has a 4-hour REI (California requires a 12-hour REI). Although no cross-resistance with other MOA 4 insecticides has been observed, Bayer recommends rotating with products outside of that MOA class. Sample rotations are found below.

    Griffin item number #70-1161: Altus 17.09% SC 64oz. Not registered in DC, HI and NY as of 5/3/17.



    Sample rotation for aphids (rotating with Altus MOA 4D)

    ProductMOACommentsItem Number
    Aria2970-3399
    Botanigard ESUNMany edible crops70-12501
    Botanigard WPUNMany edible crops; best for tomato and BCAs70-12521
    Botanigard MaxxUNMany edible crops; includes natural pyrethrin70-1253
    Endeavor9B70-1660
    Hachi-Hachi SC21A70-1795
    Kontos23Spray or drench, some edible crops70-19601
    Mainspring 28Drenches most effective for aphids70-2331
    Rycar9B70-2900


    Sample rotation for whiteflies (rotating with Altus MOA 4D)

    ProductMOACommentsItem Number
    AzaGuardUNTank mix with Botanigard; many edible crops70-1224
    Azatin OUNTank mix with Botanigard; many edible crops70-12301
    Botanigard ESUNMany edible crops70-12501
    Botanigard WPUNMany edible crops; best for tomato and BCAs70-12521
    Botanigard MaxxUNMany edible crops; includes natural pyrethrin70-1253
    Distance7CB Biotype only; some edible crops70-1465
    Fulcrum7CB Biotype only70-1710
    Judo2370-1235
    Kontos23Spray or drench; some edible crops70-19601
    Mainspring 28Apply preventatively; Bemesia only70-2331
    Molt-XUNTank mix with Botanigard; many edible crops70-2400
    Rycar9B70-2900
    Sanmite21A70-29201
    Savate 2370-2980
    Suffoil-XUNMany edible crops70-4040
    Ultra-Pure OilUNMany edible crops70-21401




    This article is intended to help applicators plan pesticide programs, but it does not replace the need to read the entire pesticide label. Pesticide labels contain more essential information than can be included in this guide, including Personal Protection Equipment (PPE), special precautions, maximum yearly application rates and more. Information include is believed to be correct, but it is the responsibility of the applicator to read and follow all label directions. Labels do change without notice. Pesticides other than those listed here may be safe, legal and effective. 

    Catch-22 for Herbs and Pesticides: Best Practices to Minimize Pesticide Use

    Herbs grown today can be used by consumers in several ways including ornamental plants, for medicinal and culinary purposes, and for homemade items like potpourri. The idea that herbs are pest-free is a common consumer perception but, regrettably, not true.

    Very few pesticides on the market are registered for use on all herbs, so scouting is essential for early detection of pests. The best way to manage pests is to place emphasis on IPM practices. With proper planning and implementation, pest detection and establishing thresholds for action can be achieved.

    Insect Control Implementation

    Examining a sticky card with a hand lens
    Yellow sticky cards, placed vertically with one-third in the plant canopy, will attract flying insects such as winged aphids, fungus gnats, shoreflies, thrips and whiteflies. The “beat test” can be used to dislodge pest from plants to provide an overview of pest presence. A hand lens or optivisor can be used to identify smaller insects not detectable on sticky cards such as spider mites, soft scales or mealybugs. Examine the undersides of the leaves and along leaf veins for presence of eggs or immature nymphs. Be observant of sticky substances on leaf surfaces, known as honeydew, that are secreted by aphids, mealybugs and soft-scale insects. Ants may also be present and will actually defend these colonies.

    If you want to stay on top of pest problems, learn to recognize symptoms or signs of pest
    activity as well as the presence of beneficial organisms. A symptom is evidence of activity such as holes in a leaf or a wilting leaf. A sign is evidence of an organism causing the damage such an aphid shed skin or mycelium growing on a leaf surface.
    Brown marmorated eggs 
    and hatching nymphs

    If growing herbs outdoors, utilize the growing degree day (GDD) to determine insect emergence times. Grower degree days are a measure of accumulated heat. Growers and landscape technicians can use this measurement of heat to predict which insects will be active at which point, in order to improve pesticide application efficacy and reduce pesticide use.

    Row covers placed over plants serve to protect them from harsh weather conditions as well as limit insect, disease and other pests. Trap plants are used in luring pests away from the main plant during critical times. Trap crops can be paced around the perimeter of the crop to be protected or within the crop, depending on the pest to be trapped. Examples of trap crops includes nasturtium to attract aphids, basil and marigold to attract thrips, or chervil to attract slugs.

    Companion plants such as marigolds, sweet alyssum, cosmos and caraway can also attract beneficial predator insects to aid in controlling pests. Biocontrol of insects and mites is becoming an increasingly popular way to manage these pests. Contact the GGSPro team for assistance in implementing a biocontrol plan for herbs.

    If chemical control is needed, choose soft or reduced-risk pesticides, referred to as biorational pesticides. Most herb growers look for products that are OMRI-certified and have zero-day or short pre-harvest intervals (PHI). Griffin offers products such as insecticidal soap, horticultural oil, neem/azadirachtin insect growth regulators and microbial products labeled for herbs. GGSPro has written a bulletin titled, “Pesticides Labeled for Herbs” that’s a useful guide for herb growers. The bulletin is free upon request. It is the grower’s responsibility to read and follow the entire pesticide label, including checking to be sure the herb you wish to treat appears on the label.

    Insecticidal soap and horticultural oils rely on thorough coverage for success. These products provide a quick knockdown but have no residual control. Applications using soaps or oils should be made when conditions are good for drying (clear, sunny days) and air temperatures are between 40-80oF.

    Insect growth regulators are often tank-mixed with other pesticides to help inhibit or interfere with part of an insect’s life cycle. A common example allowed for greenhouse herbs would be azadirachtin, found in Molt-X, AzaGuard or Azatin O for use on aphids, thrips and whitefly control. Specifically in aphid control, it works by preventing the molting process of the aphid, where the old skin is shed to allow a new one as the insect grows. These products do not control adult pests.

    Microbial products can be a bacterium, such as in DiPel, which specifically targets worm (lepidopteran) larvae. Grandevo PTO is another bacteria-based product, with broad activity against insects and mites. Fungal microbial insecticides that target many soft-body insects include Botanigard/Mycotrol/BioCeres and Preferal. Repeated applications are recommended along with a high humidity requirement to aid in these fungal spores surviving while they germinate and penetrate into the insect’s exoskeleton to cause insect mortality. Broader chemical control options include Conserve (outside herbs only), Entrust SC, and Pyganic 5.0.

    Disease Control Implementation

    Preventing diseases should be proactive rather than reactive. Knowledge of the disease pathogens most prevalent in herb production is a good place to start. The most common disease issues include Botrytis, powdery and downy mildew, Alternaria leaf spot and damping-off diseases caused by Pythiumor Rhizoctonia. Good cultural practices include avoiding high-density planting and extended leaf wetness while providing good air movement. Taken together, these steps reduce humidity and therefore foliar disease occurrence.

    Botrytis spores and stem canker on basil
    Scouting is just as important for diseases as it is for insects and mites. It’s important to examine the root system for evidence of healthy, white roots. Biofungicides such as Rootshield, Cease, Companion and Triathlon BA applied as soil drenches aid in protecting roots against root pathogens and may also reduce the need for foliar fungicides. Damping off can cause seeds to fail to germinate, or it may cause them to succumb to a stem canker that girdles the stem.

    Visible spores may or not be present on leaf or stem surfaces. Botrytis will appear as fuzzy gray-colored spores. Botrytissporulation increases significantly during humid, overcast weather conditions. Biofungicides such as Cease, Companion or Triathlon BA as well as traditional fungicides such as ZeroTol or Heritage can be applied if symptoms are observed.
    Selecting herb varieties with disease resistance, especially to powdery and downy mildews, offers reliable protection while not compromising flavor or appearance.

    Bacterial infections appear as water-soaked brown or black greasy looking spots which may be surrounded by a yellow halo when they occur on the foliage. In some cases, bacteria may be carried in the seed coat, especially on vegetables. Purchasing treated seeds where available may help eradicate infections. Bacterial infections require the pathogen inoculum, a susceptible host plant and wet conditions. Bactericides required to treat bacterial infections are limited and labels must list the herb being treated. Camelot O and Phyton 35 are labeled for several herbs, but not all.
    Bacterial leaf spot on cilantro

    Increase plant defenses against foliar pathogens by using the microbial biofungicides Regalia PTO, Fosphite and Alude. Essential Organic 1-0-1 is a root and plant stimulator that contains multiple beneficial active ingredients including kelp. Sil-Guard (0-2-5) contains potassium silicate to aid in strengthening plant cell walls and stem strength to aid in reducing stress to environmental conditions. 
    Fungicide ProductsDescriptionItem Number
    Alude2.5 Gal71-27601
    Camelot1 gal70-21201
    Cease1 gal71-13301
    Companion1 gal71-1375
    Fosphite EC1 gal71-1520
    Heritage4 oz71-1404
    Regalia PTO1 gal70-2850
    Rootshield WP10 lb71-2789
    Triathlon BA1 gal71-3040
    Insecticide ProductsDescriptionItem Number
    AzaGuard EC1 qt70-1224
    Azatin O1 qt70-12301
    BioCeres WP1 lb70-1245
    BotaniGard ES1 qt70-12501
    BotaniGard Maxx1 qt70-1253
    BotaniGard WP1 lb70-12521
    DiPel Pro1 lb70-1450
    Entrust SC1 qt70-1538
    Grandevo PTO5 lb70-1760
    M-Pede2.5 gal75-10262
    Mycotrol WPO1 lb70-2420
    Preferal1 lb70-2650
    Pyganic 5.0 Speciality1 qt70-2687
    Ultra-Pure Oil2.5 gal70-21401
    Plant StimulatorsDescriptionItem Number
    Essential Organic 1-0-11 qt166003GR
    Sil-Guard2.5 gal16GP501821
    Row CoversDescriptionItem Number
    15' x 300'DuPont 1.25 oz78-2045
    50'-500'DuPont 15' width78-2005
    50'-500'DuPont 30' width78-2010
    50'-500'DuPont 45' width78-2015
    50'-500'DuPont 60' width78-2020

    The Plants Strike Back: A SAR Wars Story

    Plants have defense systems that are activated when a plant is infected by a pathogen or suffers insect damage. The attack on the plant sets off a signal, which is carried through the plant in the form of a small molecule such as salicylic acid, jasmonic acid or ethylene, for example.

    The exact chemical signal is dependent upon the plant type and the nature of the attack. Is it an insect or a pathogen? Is it a pathogen which kills plant tissue such as Pythium or Fusarium, or a foliar infection like rust or powdery mildew? The answer determines which chemical signal is sent, and initiates a cascade of biochemical reactions within the plant, which can be quite wide-ranging. For example, the plant may produce an elevated level of antifungal proteins, or reinforce its cell walls with cellulose, lignin and proteins.

    Systemic Acquired Resistance (SAR) is like the immune system of a plant. A number of plant-protection and fertilizer products can trigger the signals of the SAR pathways in plants.
    The observable effect of this chemical signal is termed Systemic Acquired Resistance (SAR). Think of SAR as the immune system of a plant; it’s comparable to our own immune systems in that the immunity or resistance generated may be long- or short-lived, and the degree of resistance will vary by organism being presented.

    A number of plant-protection and fertilizer products can trigger the signals of the SAR pathways in plants. These products range from small molecules to living organisms. The defense signal(s) can be elicited by small molecules such as potassium phosphite, thiamine or potassium silicate.

    Potassium phosphite fungicides such as Fosphite and Alude have undergone the rigorous testing required of registered fungicides (as well as the test of time). They’re well-known for their efficacy in preventing Pythiumand Phytophthora, and for stimulating root growth. In part, the activity is due to induced resistance by the phosphite.
    Geranium (shown above) is among several crops that
    can be sensitive to excess silicate. Others include
    begonia, gerbera, pansy, petunia and tomato.

    Thiamine, or vitamin B1, is also capable of inducing a SAR signal. Thiamine is just one of many plant-boosting ingredients in the nutritional supplement Essential Organic 1-0-1 (formerly called Essential Plus). Potassium silicate and potassium phosphite are supplied in SilGuard (0-2-5). Silicate, phosphite and salicylic acid – all three – are provided in the supplement SiTKO SA 0-7-17. Some common bedding plants can be sensitive to excess silicate including begonia, geranium, gerbera, pansy, petunia and tomato, so it’s important to observe label rates and precautions.

    More complex natural products such as extracts of kelp, algae or certain terrestrial plants, as well as biochar (created by pyrolysis of wood or other plant material) have been shown to improve crop performance. The improvement seen is, in part, due to the ability of the materials to induce resistance signaling in the plants, along with any nutritional benefit, of course. Kelp extracts can be found in Growth Products’ Essential Organic 1-0-1, a root and plant stimulator product. Essential Organic is a complex product combining many beneficial ingredients for plant health, in addition to those that may elicit resistance.

    Another professional product based on plant extracts is Regalia PTO fungicide. Regalia is derived from extracts of the giant knot weed, Reynoutria sachalinensis. Regalia PTO has been shown to protect plants through induced resistance. It’s effective against a large number of fungal and bacterial pathogens, and can be used as a spray or a drench.

    Even more complex interactions occur between plants and the living bacteria and fungi we use as plant protectants including Bacillus species, Trichoderma species, mycorrhizae mixes and others. Companion, Cease, Triathlon BA, RootShield and RootShield Plus are all registered fungicides which utilize microbe-to-plant interactions to protect the plant from infection. Products based on Bacillus bacterial strains provide root and foliar protections due to multiple mechanisms, at least one of which is induction of the plants’ own resistance pathways. Bacillus fungicidal products include Companion, Cease and Triathlon BA. Similarly, the RootShield products, based on a Trichodermafungus, are used for protection against root rots, and they’ve also been shown to reduce the need for foliar fungicide applications.

    Griffin has recently added biological soil supplements by Nature’s Source to our product offering. Plant Probiotic and Biotik products both combine Bacillus, Trichoderma and other organisms in a soil amendment aimed at growth stimulation. These multi-microbial formulations aid in nutrient uptake and reduce plant stress, in part at least, by inducing the resistance system within the plant.

    Multi-microbial formulations, as found in Plant Probiotic and Biotik, aid in nutrient uptake and reduce plant stress. This happens, at least in part, by inducing the resistance system within the plant.

    This is similar to the beneficial effects of mycorrhizae, which colonize the root systems of up to 80% of all plant species in nature. Endomycorrhizae colonize inside of the root cells and are most prevalent, while ectomycorrhizae are associated with the root surface and are most prevalent in interaction with hardwood and conifer trees. The organisms form threadlike chains that function as extensions of the root, delivering water and mineral nutrients to the plant. In the symbiotic relationship that occurs, the plant feeds the mycorrhizae with sugars and more complex nutrients. Observed benefits include improved plant health and more efficient nutrient usage, both of which may lower the costs for fertilizer and fungicides.

    Mycorrhizae organisms won’t colonize all plant species equally and mycorrhizae products should be an appropriate mix for the plants being inoculated. A new line of mycorrhizae products, called MycoApply, is set to come to market – and to the Griffin product portfolio – soon. MycoApply products are based primarily on members of the Glomus genus, and multiple formulations will be available for growers to choose from.

    Analogous to vaccines and human immunity, products which utilize induced resistance should be thought of as preventative, reducing the overall need for curative actions and improving plant health. Many of these products work by multiple mechanisms, and in ways researchers are still striving to understand. However, taking advantage of the current knowledge and tapping into the plants’ ability to launch a defense can benefit your growing operation with healthier plants and reduced usage, and therefore longer lifetimes, of chemical fungicides.
    ProductsDescriptionItem Number
    Alude2.5 gal71-27601
    Cease1 gal71-13301
    Companion1 gal71-1375
    Essential Organic 1-0-11 qt166003GR
    Fosphate1 gal71-1520
    MycoApplyNAComing Soon
    Plant Biotik5 lbs67-0071
    Plant Probiotic5 lbs67-0070
    Regalia PTO1 gal70-2850
    RootShield10 lbs71-2780
    RootShield Plus10 lbs71-27911
    SilGuard2.5 gal16GP501821
    SiTKO 0-7-172.5 gal16GP30053
    Triathlon BA1 gal71-3040

    A Perennial Cover Story: How to Manage Temperature in Outdoor Production

    What to do… cover or uncover?

    Outdoor perennial production is subject to all of the natural elements and, just like the weather itself, doesn’t follow a specific set of rules. The main goal is to avoid extreme temperature fluctuations. Perennials that are warmed too much become more sensitive to cold nighttime temperatures, and more susceptible to cold damage. Keep temperature swings in check by preventing daytime temperatures from heating up your perennial crops. Let the weather report be your guide; closely monitor the forecast to help you determine when to remove or reapply coverings to your crop.


    Perennials that are warmed too much become more sensitive to cold nighttime temperatures, and more susceptible to cold damage.

    When outside temperatures begin to rise above 40°F and new plant growth starts to develop, ventilate the hoop house or uncover the beds to promote air circulation. Doing so ensures that new growth doesn’t stretch or become soft. Avoiding heat build-up on sunny winter days is very important!

    Greenhouses with roll-up sides are ideal to maintain cool temperatures if outside temperatures rise above freezing. White poly and/or positive ventilation can also be used to keep daytime air temperatures cool. The “winter protection fabric” from Griffin comes in 12’ and 15’ widths; it’s a convenient way to cover and uncover your perennials. Once warm weather arrives in the spring and remains above freezing for a period of time, removal of the thermal blanket coverings and white hoop house poly can be permanent. When you’re done with them for the season, let them dry, fold them up and store them for next season. 

    Experience teaches: “When in doubt, keep them covered.”

    Alyssum Summit Golden Yellow
    Photo courtesy of Syngenta Flowers, Inc.
    After uncovering, it’s important to address any decayed or damaged plant material that resulted from overwintering. Thorough cleanup is key to preventing problematic foliar diseases including Botrytis, powdery mildew, rust and downy mildew. Broad-spectrum fungicide sprays such as Affirm, Mural, Orkestra Intrinsic, Pageant Intrinsic or Palladium are helpful in preventing these foliage diseases, too. Specifically for outdoor use, Concert II is another good broad-spectrum option.

    A preventative broad-spectrum fungicide drench can also be applied to add extra protection from root, stem and crown diseases. Banrot, Segway, Terrazole or Truban are recommended options to keep Pythium at bay. To prevent Rhizoctonia, consider Cleary’s 3336, Emblem or Medallion.



    ProductsDescriptionitem Number
    Affirm WDG0.5 lb71-1129
    Banrot 40 WP2 lb71-1210
    Cleary's 3336 EG5 lb71-2550
    Concert II2.5 gal71-1365
    Emblem1 pt71-1570
    Medallion WDG8 oz71-16502
    Mural WDG1 lb71-1690
    Orkestra Intrinsic16 oz71-2200
    Pageant Intrinsic WG1 lb71-26801
    Palladium WDG2 lb71-2685
    Segway O16 oz71-31101
    Terrazole WP2 lb3183862
    Truban 30 WP2 lb71-3065
    Winter protection fabric6 oz, 12' x 150'81-730200
    Winter protection fabric6 oz, 15' x 150'81-730400

    New Options for the New Year: New Pesticides Bring Improved Control for Growers


    Several new pesticides came to market in late 2016, including two fungicides and one insecticide that bring improved attributes to the table. For growers who are considering the addition of these products to their toolbox for spring 2017, let’s take a closer look at each:

    Orkestra Intrinsic, from BASF, combines two active ingredients (AIs) representing modes of action 7 and 11. One active ingredient, pyraclostrobin, has been available to growers in the product Pageant Intrinsic. In addition to being a broad-spectrum preventative strobiluron fungicide, pyraclostrobin has been shown to have many plant health benefits. Tolerance to cold and drought have been documented, as well as faster and better rooting on a wide variety of plant material.

    Fluxapyroxad is the other active ingredient; it’s a new AI for greenhouse and nursery growers. It expands the number of diseases controlled, as well as providing knockdown activity for common foliar diseases such as Botrytis and powdery mildew. When applied as a soil drench, fluxapyroxad also adds Thielaviopsis control.

    Orkestra Intrinsic is formulated as a liquid suspension concentrate. Foliar sprays control Botrytis, downy mildew and powdery mildew, as well as many leaf spot diseases, crown rots and stem blights.  Soil drenches provide preventative control of Fusarium, Rhizoctonia and Sclerotinia, and suppression of Phytophthora, Pythium and Thielaviopsis.

    Impatiens downy mildew
    It is labeled for use on ornamental plants in greenhouses, shade houses, lathhouses, outdoor nurseries, retail nurseries and landscapes. Orkestra has a 12-hour REI, making it suitable for inclusion in many disease programs. Registered in all states except California.    

    Segovis is a unique new fungicide from Syngenta. Its active ingredient is oxathiapiprolin, designated as mode of action group U15. Segovis brings with it the longest length of residual control of downy mildew on the market when applied as a soil drench—up to 6 weeks depending on the drench rate applied. This is very welcome news to growers producing Impatiens walleriana that are defending their crops from impatiens downy mildew.

    Segovis brings the longest length of residual control of downy mildew on the market when applied as a soil drench—up to 6 weeks depending on the drench rate applied.

    Segovis is also highly effective against Phytophthora when applied by spray or drench. Aerial Phytophthora has been an in increasing problem for spring petunia growers, especially in the propagation of vegetative cuttings. Best applied preventatively or at the first sign of disease, Segovis is labeled for ornamentals in greenhouses, shade houses, lathhouses, outdoor nurseries and commercial landscapes. Segovis is a good tank-mix partner, has just a 4-hour REI and no signal words on the label. Not registered in New York.
    Aerial Phytophthora on vegetative petunia
     


    BotaniGard MAXX from Bioworks is a dual active-ingredient insecticide with the mode of action group 3A. Many growers are familiar with BotaniGard; it utilizes the microbial insecticide Beauveria bassianastrain GHA, which works by germinating on several soft-bodied insects and making penetration, causing death over a period of a few to several days. BotaniGard MAXX adds a second active ingredient, a natural pyrethrin, to add a quick knockdown of several insects. Used as a foliar spray it provides control of aphids, thrips, whitefly, mealybugs, leafhoppers, plants bugs and many more.

    Many growers are familiar with BotaniGard. BotaniGard MAXX adds a second active ingredient to add a quick knockdown of several insects.

    BotaniGard MAXX is labeled for ornamentals, herbs, vegetables, fruits and nuts in greenhouses, shade houses, nursery, field, landscape, turf and interiorscapes. It has a 4-hour REI, 0-day PHI, excellent plant safety and can be used through a variety of low-volume applicators. Bioworks publishes a compatibility guide to assist with tank mixing. Registered in all states except California.    



    ProductDescriptionItem Number
    Orkestra Intrinsic16 oz71-2200
    Segovis1 pt71-3100
    BotaniGard MAXX1 pt70-1253
    BotaniGard MAXX1 gal70-1254
    BotaniGard MAXX2.5 gal70-1255

    Rooting Out Root Rots: How to Defeat Pythium and Phytophthora


    Soilborne pathogens cause significant losses to ornamental and vegetable crops in greenhouses and nurseries worldwide. Pythium and Phytophthora are among the most common of these pathogens. Such pathogens are commonly referred to as “water mold” pathogens rather than true fungi because they’re associated with wet conditions, wherein they produce swimming zoospores. These pathogens lead to root and crown rots, and can cause disease if splashed onto plant foliage.

    Both Pythium and Phytophthora are natural soil inhabitants and gain access into production areas via irrigation water, soil, airborne spores, insects, weeds, equipment and footwear. They can also carryover in crops harboring the pathogen. 

    Pythium root rot on petunia
    Pythium is characterized by brown patches on roots. A diagnostic tool for Pythium is the ability to gently slide the outer root tissue off the root, leaving only the inner cortex. Infected plants will generally show mild-to-severe yellowing prior to collapse. Optimum soil temperatures for Pythium vary with the pathogen species: P. aphanidermatum is 95oF, P. irregulare is 86oF and P. ultimum is 76-86oF.

    Pythium is an opportunistic disease. It easily spreads through water, and tends to infect plants that are already subject to stress. Fungus gnats are also known to spread Pythium in the greenhouse environment.

    Cultural management is key in reducing Pythium risk: Produce crops within their ideal temperature range. Avoid strong wet/dry media moisture cycles. Avoiding excessive fertilization that can contribute to high media-soluble salts (EC). Practice strong sanitation prior to and during crop production. Be sure to filter or treat recirculated water.

    Phytophthora root rot and aerial blight on fuchsia

    Phytophthora is a fast-moving pathogen. It’s characterized by decline symptoms including leaf yellowing, stunting, wilting and blighting of petioles. This pathogen often leads to plant death in a short period of time. Root symptoms are similar to Pythium except for root sloughing. Examination by cutting into the crown area may reveal a reddish brown discoloration and dark streaks moving up the vascular system.

    Phytophthora onset is favored by high soil moisture and warm soil temperatures. Like Pythium, optimum soil temperatures will vary with the Phytophthora species. Phytophthora overwinters in soil/media mainly as dormant resting spores (oospores or chlamydospores).

     
    We're fortunate to have a range of choices, both chemical and biofungicides, labeled to prevent and control Pythium and Phytophthora pathogens.

    We’re fortunate to have a range of choices, both chemical and biofungicides, labeled to prevent and control Pythium and Phytophthora pathogens when applied as drenches. Biological fungicides must be applied preventatively as they have no curative properties. These fungicides fit nicely into a traditional IPM program as being compatible with most chemical fungicides if needed. Traditional chemical fungicides may be applied preventatively as well as curatively. All labels must be examined carefully for crops being treated, and for application intervals.

    The GGSPro Technical Reference Guide contains important mode of action (MOA) information to help growers make good fungicide rota­tion choices. The GGSPro team is available to answer your inquiries as well. Pesticides other than those mentioned here may also be legal, safe and effective.


    Product Description Biological Chemical Ornamental Edible Item no.
    Actinovate 18 oz X X X 31007318
    Alude
    Fosphite
    2.5 gal
    1 gal
    X X X 71-27601
    71-1520
    Banrot WP 2 lb X X 71-1210
    Cease
    Companion
    Triathlon BA
    1 gal
    1 gal
    1 gal
    X X X 71-13301
    71-1375
    71-3040
    Rootshield Plus G
    Rootshield Plus WP
    1 lb
    1 lb
    X 71-27911
    71-27951
    Segway O 16 oz X X 71-31101
    Subdue MAXX 1 qt X X 71-2979
    Terrazole L
    Terrazole WP
    Truban EC
    Truban WP
    1 qt
    2 lb
    1 qt
    2 lb
    X X 71-3025
    3183862
    71-3070
    71-3065
    ZeroTol 2.0 2.5 gal X X X 71-35501

    Maintenance Essentials: How to Keep Your Fertilizer Injector in Top Condition

    How many times have you heard the statement, “If you take care of your equipment, it’ll last longer?” We can all agree that, eventually, your car will need an oil change, your air conditioner will need refrigerant and your lawnmower blades will need sharpening. Where does your fertilizer injector rank when it comes to maintenance?

    Most greenhouse operations deliver the majority of their fertilizer through the irrigation system, making fertilizer injectors essential. An injector that’s not working properly can result in increased crop times and poor plant quality. Lela Kelly from Dosatron says some growers believe that, because the injector is sucking liquid and the stock tank isn’t as full, it must be functioning properly. This isn’t always true! It’s best to check your injector for accuracy and put it on a yearly maintenance program.

    Just because your injector is sucking liquid and the stock tank isn’t as full, doesn't mean it's functioning properly.

    To check the calibration of your fertilizer injector, start with a calibrated conductivity/EC meter and measure the conductivity of a clear water sample. Next, mix up a fertilizer stock solution to yield a 200-ppm nitrogen solution through the injector at 1:100. Turn the injector on and allow the fertilizer to flow through the hose for several minutes. Collect at least a quart of fertilizer solution to ensure a uniform sample,and use the conductivity/EC meter to measure the conductivity of that fertilizer solution.

    Take this conductivity reading from the fertilizer and subtract the conductivity reading of the clear water to yield the true conductivity of the fertilizer solution. Compare the reading with the EC or conductivity reading for 200-ppm nitrogen on the fertilizer bag. If the conductivity reading is within 5-10% of the target EC or conductivity, your fertilizer injector is working properly. If this conductivity reading significantly deviates from the target, the injector isn’t working properly and should be repaired, re-built or replaced.

    A physical calibration test can also be conducted by setting your Dosatron to 1:128, (1:128 = 1 ounce to 1 gallon of water). Fill a container with 5 ounces of fertilizer solution and place the Dosatron suction hose inside. Turn your Dosatron on so that it sucks up the 5 ounces. When the 5 ounces of fertilizer solution is gone, it should have yielded a 5-gallon bucket of fertilizer solution. This indicates that the injector is calibrated. If the injector doesn’t deliver enough fertilize, it’s an immediate indication that it’s time for a seal kit/component kit replacement.

    Dosatron fertilizer injectors are powered by water pressure, using the flow of water in your irrigation system to drive a piston pump and using patented technology to deliver a precise dose of fertilizer or chemicals through the irrigation lines. It’s important to set up your injector system properly, using both a filter and a check valve. Dosatron recommends a 200-micron filter to keep all debris from effecting the action of the unit. A check valve is also important. “Back Flow” water can impact the unit with as much as four times the initial water pressure, and can cause severe damage to the injector.


    Quick Steps to Maintain Your Dosatron Injector

      Dosatron Mini-Maintenance Kit
      Image courtesy of Dosatron
    1. Purchase a ‘Do It Yourself’ Mini-Maintenance Kit that includes the components and Dosa-Klean for your size Dosatron.
    2. Before and after Dosa-Klean
      Image courtesy of Dosatron
      The night prior to changing the maintenance kit, take apart your Dosatron and thoroughly rinse all parts in clean water to remove any chemicals.
    3. Dissolve one packet of Dosa-Klean into one gallon of water. Larger injector units may require two packets per two gallons of water.
    4. Soak overnight or up to 48 hours in the Dosa-Klean solution, then rinse thoroughly. Dosa-Klean will remove rust, mineral deposits and calcifications without scrubbing.
    5. Next, it’s important to install all of the new components included in the maintenance kit.
    6. Put the injector back together. If needed, Dosatron includes instructions with pictures to assist you.
    7. Finish by conducting another calibration test, to ensure everything is injecting properly.
    Note: If your Dosatron is not clicking, this is not an issue that a seal kit/component kit will fix. It’s indicative of a motor problem, and you should call Dosatron’s Customer Service for assistance at 800-523-8499.
    Product Description Item no.
    Dosatron Mini-Maintenance Kit D14MZ2 14-GPM Unit 219-000
    Dosatron Mini-Maintenance Kit D45RE15 20-GPM Unit 219-001
    Dosatron Mini-Maintenance Kit D8R 40-GPM Unit 219-003
    Dosatron Mini-Maintenance Kit D8RE2 40-GPM Unit 219-005
    Dosatron Mini-Maintenance Kit D20S 100-GPM Unit 219-004
    Dosatron Dosa-Klean Single-Use Packet -- 85 gms. 33-2633
    Dosatron Dosa-Klean Economy Pail -- 3 lbs. 33-2636

    In Defense of Cyclamen: How to Fight Off Foliar Diseases

    As the weather begins the slow slide into the darker and more humid conditions of fall and winter, cyclamen crops require extra attention. Cyclamen benefit from the cooler temperatures after a summer of high temperature stress but, as the crop canopy fills in, the increase in humidity poses challenges. Specifically, foliar diseases can become more common at this stage of the crop.

    Sierra Synchro cyclamen on the bench.
    Photo courtesy of Syngenta Flowers.
    Botrytis can gain a foothold during the fall and winter due to the dense plant canopy. Look for gray, fuzzy growth under the canopy. Under high disease pressure, petioles and developing flower stalks can be girdled near the corm. Flower damage shows as darkly pigmented areas or dark spotting on the petals. To help keep Botrytis at bay, remove senesced leaves and flowers, increase airflow and, to the extent possible, keep the relative humidity in check.

    Overfertilization can predispose plants to foliar diseases, as well as crown and root rots. Keep close tabs on soil EC levels and leach if needed to keep EC levels below 1.25 via the saturated paste method. Many cyclamen growers rely on calcium nitrate and potassium nitrate as the backbone of their cyclamen fertilizer program. GGSPro has a bulletin on cyclamen production that provides detailed nutritional information. Fungicides are often needed to augment even the best cultural practices. Resistance is a significant issue when it comes to Botrytis,so take advantage of the chart at the end of this table that sorts effective fungicides by mode of action.


    Cyclamen benefit from the cooler temperatures of fall and winter but, as the crop canopy fills in, foliar diseases can become more common at this stage of the crop.

    Unfortunately, Botrytis isn’t the only foliar disease cyclamen growers need to prepare for. Two anthracnose diseases also affect cyclamen. The less serious Colletotrichum causes small brown spots on leaves. The more serious Gleosporium(Cryptocline) attacks young petioles, with distinctive drying and malformation of the young tissue. Gleosporium can also attack older tissue and flower buds, resulting in drying and distortion. The cultural techniques discussed for Botrytis will also be helpful here. In some cases, fungicides that control Botrytis are also effective against anthracnose diseases. Consult the table below for assistance in sorting through the available options.


    Cyclamen displaying INSV symptoms
    Viruses can produce distinct foliar symptoms that can be confused with other foliar problems. The thrips-transmitted tospoviruses, INSV and TMSV, both occur in cyclamen. Watch for ring spots, mosaic patterns, atypical leaf coloration (yellow, bronze or brown) and distortion. Should you discover any of these symptoms during your scouting efforts, discard effected plants immediately and work to control thrips. GGSPro can advise regarding biocontrol options, as well as insecticides that have shown good plant safety on cyclamen.

    Always read and follow the pesticide label. Products other than those mentioned may also be safe and effective.


    ProductDescriptionMode of ActionBotrytisAnthracnoseItem no.
    Affirm WDG 0.5 lb. 19 X X 71-1129
    Camelot O* 1 gal. M1 X 70-21202
    Cease 1 gal. 44 X X 71-13301
    Daconil Ultrex* 5 lbs. M5 X X 71-1420
    Emblem 1 pt. 12 X X 71-1570
    Medallion WDG 8 oz. 12 X X 71-16502
    Mural WDG 1 lb. 7&11 X X 71-1690
    Nordox 75 WG** 12.5 lbs. M1 X 71-1700
    Orkestra Intrinsic* 16 oz. 7&11 X X 71-2200
    Pageant Intrinsic WG 1 lb. 7&11 X X 71-26801
    Palladium WDG 2 lbs. 9&12 X X 71-2685
    Phyton 35* 1 gal. M1 X 71-2737
    Protect DF** 6 lbs. M3 X 71-2748
    Trigo 1 lb. 3&11 X X Coming Soon
    Triathlon BA 1 gal. 44 X X 71-3040
    * Cyclamen bloom safety unknown
    ** Residue may be noticeable

    Managing the 3 Ms of Poinsettias: Manganese, Molybdenum and Magnesium

    The pH of soilless media plays a large role in the availability of nutrients to plants. Most micronutrients tend to be more available to plants at low media pH. For crops inefficient at uptake of micronutrients, pH above 6.0 may result in micronutrient deficiencies. For crops efficient at micronutrient uptake, such as poinsettias, pH below 5.8 can cause micronutrient toxicities.

    Some crops and nutrients are more affected by media pH than others. Poinsettias and the nutrients Iron (Fe), manganese (Mn) and molybdenum (Mo) are good examples. Fe and Mn are more available to plants as the pH drops below 6.2. Molybdenum and poinsettias present an opposite situation. Molybdenum is more available at higher pH.

    To avoid a combined problem of reduced availability and low uptake, it’s essential to maintain poinsettias at a soil pH in the range of 6.0-6.5.

    Nutrients can be classified according to how mobile they are within the plant. The differences in nutrient mobility lead to differences in symptom expression, which can be recognized and used for diagnosis of nutrient deficiency or toxicity. Nutrients are classified as: mobile, immobile or intermediate.

    1. Mobile nutrients move easily within the plant. The lower leaves are able to give up these nutrients to supply the younger leaves. Therefore, deficiency symptoms first express on the lower leaves of the plant. Mobile nutrients include nitrogen (N), phosphorus (P), potassium (K) and magnesium (Mg). 
    2. Immobile nutrients don’t move easily through the plant. The lower leaves are unable to supply nutrients to the younger foliage. Deficiency symptoms first express on the youngest leaves. Immobile nutrients include boron (B), calcium (Ca), copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn).
    3. With intermediate mobility, early deficiency symptoms can occur anywhere on the plant. Somewhat mobile nutrients include molybdenum (Mo) and sulfur (S). 

    Manganese (Mn) Deficiency

    Manganese deficiency
    Poinsettias with manganese deficiency exhibit symptoms including interveinal chlorosis starting with the youngest growth. The veins will appear sunken while the tissue between the veins looks raised. Frequent media analysis should be conducted to treat before symptoms appear. Maintain media pH below 6.2 to improve manganese availability.

    Mn symptoms can be easily confused with iron deficiency. To distinguish from an iron deficiency, look for the characteristic change in leaf texture to a corrugated look, sometimes similar to an orange peel in appearance—that’s typical of manganese. High levels of iron in the media inhibit the uptake of manganese. If media tests confirm a deficiency, apply a corrective drench of chelated manganese at 1.0-1.5 oz per 100 gal. Retest the media before making additional applications.

    Molybdenum (Mo) Deficiency

    Molybdenum deficiency
    Poinsettias have a unique requirement for molybdenum and are produced at a higher media pH to accommodate this need. Molybdenum becomes more available as soil pH rises above 6.0. Growers incorporate poinsettia feeds with molybdenum as a part of the fertilizer regime, but they often have to supplement with additional ammonium molybdate. This is especially true when using standard peat-lite fertilizers. Some of the newer poinsettia cultivars appear to have higher Mo requirements. If you’re not using a fertilizer specifically for poinsettias with elevated Mo, or soil tests indicate Mo is lacking, you can make pulse treatments or opt for a constant injection plan, both of which are explained in a bulletin from GGSPro titled, “Molybdenum Applications for Poinsettias.”

    Molybdenum deficiencies are slow to express and should be treated preventatively in the months of September and October. Marginal leaf yellowing and cupping with leaf scorch distorted symptoms usually occur in the mid-region of the foliage right below the bracts. Molybdenum applications made after the symptoms appear, unfortunately, won’t reverse these symptoms. Large, well-formed bracts will often hide those symptoms. Growers experiencing low soil pH may have to rely on a foliar spray instead of a soil drench, although correcting the soil pH is recommended.

    Magnesium (Mg) Deficiency

    Magnesium deficiency
    Magnesium deficiency symptoms begin with an overall diminished green foliage color. Left untreated, symptoms progress to interveinal chlorosis first appearing on the lowest leaves. Downward cupping and a thicker texture may also occur with more severe deficiencies. Magnesium deficiency is often an indication that the overall fertility level of the crop is too low.

    Apply magnesium as a one-time corrective drench application or as a part of a constant liquid feed program. Epsom salts are an inexpensive option to provide magnesium, and can be added to most fertilizers with the exception of those containing calcium (e.g., 15-0-15, 13-2-13). The one-time corrective rate for Epsom salts is 8 oz per 100 gal. Constant injection of Epsom salts can be done at lower rates, generally 2-3 oz per 100 gal based on the amount of magnesium in the irrigation water, including the fertilizer.


    ProductDescriptionItem No
    Chelated manganese1 lb.91-2193
    Ammonium molybdate1 lb.91-2198
    Magnesium sulfate/Epsom salts55 lbs.14MGSUL55

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