Page 15 - Griffin Gazette - March 2026

By Karen Stever, Ph.D., GGSPro Technical Specialist

Early spring ornamental crops are maturing in the greenhouse at this time of year, whether you are in
the East, West, North, or South. It may even be close to shipping time in warmer climates. Too often,
scouting is pushed to the back burner when the foliage fills in, providing shelter and ample feeding
opportunities for pests (Figure 1). Discovering an infestation of aphids, thrips, whiteflies, or mites during
the shipping process is one fire no grower looks forward to putting out.

Mid or late-season drenches are cheap insurance to prevent pest outbreaks that can disrupt sales
or shipping. What to apply and when can be dependent on your historical and regional pest issues.
Available drench products are not sufficiently effective to rid a crop of mealybugs and are no longer
recommended. Spider mites and broad mite species are also not controlled by a “come from behind”
drench application. Kontos is the only drench product that provides protection against common mite
species as well as aphids and thrips. As such, a Kontos drench must be applied early, typically as
soon as plants are rooted in post-transplant. A spray program is typically the best approach for both
mealybugs and spider mites – please contact GGSPro to assist you with an effective spray schedule to
clean up active infestations for these challenging pests.
Figure 1: Full greenhouse - abundant opportunities for pests to hide and feed.