Page 13 - Griffin Gazette Spring 2016
P. 13
be one of the first crops to show powdery Gerbera daisy, powdery mildew Interveinal chlorosis of the older leaves
mildew under conducive conditions of dry Gerbera daisy, thrips feeding foliage damage indicates a magnesium deficiency.
foliage and high humidity. The best way to Gerbera daisy, thrips flower damage Magnesium deficiencies are quickly reversed
avoid disease development is to manage the with an application of Epsom salts at 8
greenhouse environment to reduce humidity oz/100 gal.
by venting and/or heating. However, the
weather doesn’t always cooperate, and Challenge #4: Poor Flower Development
preventative treatments are warranted when A gerbera crop without flowers isn’t likely
conditions are likely to support disease. to result in good sell-thru at retail. The most
One of the best options for prevention of common causes of low flower count in
powdery mildew just happens to be an gerbera relate to a lack of light reaching the
OMRI-listed, soft chemistry: Regalia PTO. crown. Be sure to avoid deep planting of the
Sprayed ahead of the onset of disease, liners, as burying the growing point will nearly
Regalia PTO will effectively prevent powdery guarantee reduced flowering and reduce
mildew on gerbera. Cease, Mural, Pageant crop uniformity. Even when planted to the
Intrinsic, Protect DF or Triathlon BA are proper depth, crowding will reduce flower
also good options for prevention. If disease count through shading. This effect can occur
does develop, turn to Affirm, Eagle, Milstop, at any point in the production cycle, including
Palladium or Strike Plus. the plug or liner stage. Avoid shading by
planting young plants on time and space
Challenge #3: Nutrient Deficiencies crops as soon as neighboring leaves touch.
Gerbera roots have a high demand
for oxygen, and the plants greatly A little attention to avoiding the most common
resent saturated conditions caused by production problems for gerbera will result in
overwatering. Saturated conditions also a smoother season and beautiful plants with
limit uptake of boron and calcium. Resulting strong impulse appeal. The end result is well
deficiency symptoms show as distortion of worth the extra attention during production.
the young tissue: Look for spoon-shaped
leaves and narrow petioles. Deficiencies Not all products are registered in all states.
can be minimized with application of boron Some pesticides are restricted-use in some
and inclusion of calcium-based feeds in the states or regions and not others. It is the
fertilizer rotation. However, the best way to responsibility of the applicator to read and
avoid these deficiencies is by encouraging follow all label directions, remembering that
strong transpiration with adequate plant labels may change. Other products may
spacing, good airflow from HAF fans, also be safe and effective. Rates, application
use of a well-drained media and careful methods and edible status are detailed in the
watering practices. GGSPro I&F Guides.
