How to Control Boxwood Spider Mites

Boxwood spider mites have claimed the lives of many boxwood tree leaves. These tan-colored mites eat leaves, causing them to turn from yellow to brown and often fall off prematurely. Some gardeners confuse the mites with spiders, because of their long front legs; however, these pests are indeed mites. Although the chances of the mites killing the tree are low, they do cause damage to the vegetation, making their removal a must.

Garden hose

Predatory mites

Miticides

Insecticidal oils or soaps

Spray the tree with water from your garden hose. The strong current knocks the mites and its eggs off of the tree. Squirt the undersides of the leaves in addition to the tops, as mites will often hide and lay their eggs in such locations.

Release predatory mites onto affected trees. Predatory mites, such as the Amblyseius, Phytoseilus and Metaseilus species, eat the boxwood spider mites without harming the tree. The mites also prevent future mite infestations from occurring.

Apply miticides to affected trees. Miticides that contain ingredients such as diazinon, malathion and acephate are typically effective against the mites. Spray most miticides directly on the tree; however, read the product's label for its specific instructions, as they can vary per brand.

Apply insecticidal oils and soaps to the tree. Insecticidal oils and soaps are similar to miticides, except they contain fewer chemicals and as a result are less harmful to the environment. Apply the products directly to the affected leaves, as they work by contact. Follow the directions on the product's label for information on dilution, as some brands require modifying the products before applying them to the trees.

Predatory mites, miticides and insecticidal oils and soaps may be found at hardware and home and garden stores.

Japanese boxwoods are usually less susceptible to boxwood infestations than other varieties.