Page 26 - Griffin Gazette - March 2025

3. Mid-Season - Adjust BCA rates as the canopy FIGURE 1: Lacewing Larvae (Chrysoperla carnea) used
develops for problem crops. as a primary control for aphids but also a generalist for
thrips and mealybugs.
• BCAs at the soil level only need to be introduced to new
transplants, although S. feltiae is useful as a curative for FIGURE 2: Beneficial nematodes (S. feltiae) for fungus
fungus gnat or thrips outbreaks. gnat larvae and thrips pupae in the soil.

• Continue regular releases of A. cucumeris throughout
the crop cycle; consider replacing it with A. swirskii when
the greenhouse reaches 77°F average daily temperature
(ADT).

• Crops that frequently develop spider-mite issues receive
releases of P. persimilis as soon as the pest is detected.

4. Late Season - Consider conventional chemical
applications during favorable pest breeding
conditions.

• Oil-based products are not compatible with BCAs but
have short residual effects. They are a key element in
rotations targeting highly resistant pests such as spider
mites and mealybugs.

• There are late-season drenches that have minimal
impacts on BCAs (e.g., Mainspring, Kontos, Endeavor,
and Altus).

• By reserving chemistry for this moment, we can expect
that several bloom-safe chemistries that target specific
pests will be more effective. Some chemistry is BCA
compatible, but economics will dictate whether it is
realistic to continue releases on a specific problem crop.

One successful strategy for hanging baskets reverses the order of application above and introduces BCA
compatible drenches of conventional chemistry early in the crop cycle. Aphids are often a late season problem
in hanging baskets, even with a well-executed BCA program. In this scenario, we treat the baskets with BCAs
and biopesticides while they are on the bench, including a sachet of A. cucumeris before hanging for five weeks
of residual thrips control. Once hung, they are drenched with long-lasting chemistry that protects them from
other pests, such as aphids, for four to six weeks, or potentially well into the crop cycle.

While biological control programs may not be suitable for every grower or situation, understanding the principles
behind their use will help growers develop a comprehensive Integrated Pest Management (IPM) strategy. This
approach maximizes the effectiveness of all available tools, improving overall pest control outcomes. It’s
important to note that not all microbial-based products are labeled for every crop, so growers should ensure
they are following the appropriate regulations for their specific crops and state.

26 | GRIFFIN GAZETTE 2025