Spider Mites on Hydrangea

The hydrangea is a popular flower with home gardeners. There are over 23 different species of hydrangeas, all of which can be affected by pests such as spider mites. Spider mites are usually worst during hot, dry weather.

Identification

• Spider mites are members of the arachnid family and develop from eggs. During hot, dry weather spider mites grow rapidly, reaching maturity in as little as one week after hatching. Mature females produce several dozen eggs each day for two weeks, which leads to high spider mite populations.

Significance

• According to The United States National Arboretum, hydrangeas are susceptible to spider mite infestations. Spider mites are so small that they cannot be seen without the aid of a microscope, but the tell-tale webbing left between the hydrangea leaves signals their presence.

Prevention/Solution

• Spider mites are often difficult for the casual home gardener to eliminate using pesticides because pesticides kill their natural predators; they are also resistant to many types of chemicals. Spraying your hydrangeas with a hard stream of water can eliminate mites. Chemical control methods that are designed specifically for spider mite elimination are the most successful.