Change from white, yellow or orange in color to brown or black throughout life cycle
Streak, distort and discolor flower petals and leaves
Most damaging species are the western flower thrips
Multiply faster during periods of warm, dry weather
Thrips are tiny, cylindrical insects with short antennae and two sets of wings. Often hidden in protective areas of flowers or developing buds, thrips often cause severe damage before they're detected. During the nymph stage, thrips are white, yellow or orange in color. Adult thrips are brown or black.
Similar to spider mites, thrips damage plants with their scraping mouths. These harmful insects streak, distort and discolor flower petals and leaves. They also excrete little, black spots of feces and give plants a silvery, speckled appearance.
Perhaps the most damaging thrips species are the western flower thrips. Not only does the species reproduce rapidly, it also transmits viral diseases (e.g., the tomato spotted wilt virus) from plant to plant.
Thrips tend to multiply faster during periods of warm, dry weather. Eggs are laid on plant tissue and inserted into small slits.
Thrips infest several types of crops, including bedding and garden plants, potted plants and cut flowers.
To control adult thrips apply a mixture of eight ounces of Mavrik Aquaflow® insecticide, four ounces of piperonyl butoxide and two pounds of brown sugar per 100 gallons of water to treat 20,000 square feet. The application should be made twice, five days apart. Ideally plants should be sprayed early before heavy populations develop. A third application may need to be made under heavy infestations.