Spider mites are very small arachnids (spider family) that infest a wide range of horticulturally and agriculturally important crops. These mites are very small, almost invisible to the naked eye. Spider mites prefer warm dry weather because rain washes them off of plants.
Host Plants
Virtually all plants are susceptible to infestation. Greenhouse plants are especially vulnerable as are outdoor herbaceous perennials. Many ornamental shade trees and landscape shrubs such as conifers, oak, buckeye, and many others may be infested.
Damage
The most common mite affect ing landscape plants is the Two Spotted Spider Mite (TSSM). TSSM causes stippling, flecking and speckling of leaves of ornamental trees, shrubs, and herbaceous perennials. Damage may occur outdoors in the summer when there has been little rain and temperatures are very high.
Control
Rinsing the plants a few times per week with a strong stream of water can wash spider mites off of the plant reducing populations. Sometimes you can avoid having to use pesticides in this way.
