Western Flower Thrips

What it looks like

Western flower thrips are very small, slender insects with fringed wings, and are common in greenhouses and gardens. Adults are about 1/32 inch long and yellowish to brown.

In spring, adult thrips insert their eggs into plant leaves or stems. The eggs hatch in a few days, sooner in warm weather. The wingless young (nymphs) feed and go through two more stages, then change into pupae in the soil before coming out as new adults. Adults and pupae spend the winter in the soil.

The whole life cycle can take as little as a few weeks, or much longer, depending on temperature and other conditions. That's why thrips are a bigger problem in warmer months, when the life cycle is shorter.

Damage

Thrips usually feed in large groups. They damage plants by sucking out the juice, and by spreading serious plant diseases such as impatiens necrotic spot virus (INSV) and tomato spotted wilt virus (TSWV). Young plants are especially at risk.

Thrips can cause stunted growth, discolored or speckled (stippled) leaves, scarring, and smaller harvests.

How nematodes help

The beneficial nematodes in BioLogic's products hunt down and kill thrips pupae in the soil. Killing the pupae stops the life cycle, so new adults don't emerge.

How to apply

Apply Scanmask to the soil or growing media under your plants, where thrips pupate. Treat anytime the soil is not frozen, especially in the warmer months when thrips are the biggest problem.

See How to apply for step-by-step directions, or use the calculator on the Scanmask Spray page to see how much you need.