Hi George –
I would highly reccomend Spinosad for your thrip problem. It is a microbial insecticide that must be eaten to be effective, meaning your beneficial nematodes and lacewings will be minimally affected by its application. Blue Sticky Traps are another great product that could be used for monitoring your pests. Thrips are attracted to the blue color, this visual attractant allows one to monitor the size of population and life cycle stages. This information can help you decide if it’s necessary to apply another round of spinosad, or if nematodes or lacewings may be more effective.
Timing is crucial to a proper IPM management plan. Applying nematodes in spring and/or fall before the pests emerge from the soil is one part of the equation. Timing pesticide applications, environmental or physical control methods and beneficial insect releases would be another. Thrips can be sprayed off the plant with high pressured water, using a product such as the Bug Blaster. If going this route, spray in the morning or before the heat of the day. Plant must dry completely before night falls to avoid powdery mildew and other foliar diseases.
I would suggest a foliar spray down, followed by an application of spinosad, and a release of lacewing larvae one-two days after. Nematodes can be applied at anytime, but will be most effective in spring and fall to control populations that overwinter in the soil.
Good Luck!
.
