Leaves are wilted, stippled, yellowing, and dirty. Leaves may dry out and drop. There may be fine webbing over flower buds and around leaves. Plants lose vigor. To check for twospotted spider mites, hold a sheet of white paper underneath an affected leaf and tap the leaf sharply. Minute specks the size of pepper grains will drop to the paper and begin to crawl around.
Apply an insecticide labeled for this pest, following instructions on the label. Mites are difficult to control because they reproduce so rapidly. Hose down plants with a high-pressure nozzle every few days to knock off webs and mites.