Page 25 - Griffin Gazette - March 2025

Microbial pesticides including azadirachtin products (e.g., Aza-Direct, Azatin O,
AzaGuard EC, and Molt-X), Beauveria bassiana (e.g., BotaniGard WP/ES and Velifer),
Bacillus-based formulations (e.g., Cease, Triathlon BA, Stargus, Gnatrol, and Dipel Pro),
and Grandevo CG, offer significant advantages over conventional chemical pesticides.
These biological products typically exhibit little to no resistance development, shorter
restricted entry intervals (REIs), and require minimal personal protective equipment
(PPE), all while providing good plant safety. These benefits make microbial pesticides an
attractive addition to any grower’s pest management toolkit.

While oil and insecticidal soap products are not considered biological pesticides, they
fall into the category of ‘softer’ chemistry, like bios. These products are also useful for
resistance management due to their physical modes of action. However, it's important to
be aware that certain oil, soap, and azadirachtin-based products can cause phytotoxicity
if misused. To minimize risk, avoid applying these products during periods conducive to
slow drying conditions or high temperatures and humidity (particularly when temperatures
exceed 85°F).

By reserving conventional pesticides for cleanup before sales or as a "rescue" option
during outbreaks, growers can protect their crops and maintain the long-term efficacy of
both biological and chemical pest control strategies.

This following strategy explores options for common pest challenges in ornamental
greenhouse production and offers guidance on effectively using biological products to
support a successful growing season.

INTEGRATION STRATEGIES FOR BENCH CROPS
An effective strategy for bench crops should include regular releases of BCAs and
targeted sprays of biopesticides to help reduce pest pressure without jeopardizing BCA
populations. Treat all incoming materials with biopesticides while still in the plug stage.

1. Early Season - Preventative BCA releases begin as soon as the benches are full.

• Start with S. feltiae, Stratiolaelaps scimitus, and Dalotia coriaria at the soil level for
fungus gnat larvae and late stages thrips as they fall to the soil to pupate.

• Early releases of A. cucumeris will hunt in leaf buds for the first stage of thrips larvae.
• Chyrsoperla carnea (Lacewing larvae) are good generalist hunters; excellent at

controlling aphids. Additionally, a combination of the parasitoid wasps A. colemani
and A. ervi will parasitize the four most common species of greenhouse aphid.

2. Early Season - Begin targeted sprays of biopesticides in response to weekly
scouting reports.
• If releases are made biweekly, time the sprays to get a “knockdown” of the pest
population 3-4 days prior to the next release.
• Azadirachtin products (natural insect growth regulators) have a synergistic effect
when combined with biopesticides (e.g., Azatin O + BotaniGard WP).

Continued 

GRIFFIN GAZETTE 2025 | 25