Pest Alert:Attack of the Azalea Caterpillar

Azalea Caterpillar

Azalea caterpillars are showing up on azaleas this time of year. You might have seen moths about 2 inches long with orangish-brown banded wings flying around your azaleas. The moths are sort of pretty until the lay their 100s of eggs on your favorite azalea and the caterpillars start eating.


Azalea caterpillars primarily attack azaleas, especially the “indica” varieties. They will however feed on blueberry, viburnums, and apples. This large (2 inches at maturity), strikingly marked caterpillar is an occasional pest of azaleas throughout the South. Newly-hatched azalea caterpillars are yellow with longitudinal reddish stripes, but their appearance changes markedly as they grow. Older caterpillars are black, checkered with yellow or white, and have a reddish-orange head and legs. If you disturb the caterpillars they will raise their heads and tails raised, creating a broad u-shape.


Newly-hatched larvae feed together on the undersides of leaves, causing leaf skeletonization. As larvae grow they spread out and feed individually, causing progressively greater amounts of defoliation. Heavy infestations can cause total defoliation of entire plantings of azaleas. As with most caterpillars, 80 to 90 percent of the total leaf area that a single caterpillar will eat during its life is eaten during the last 3 to 4 days before pupation. This is why severe defoliation can seem so sudden. Plants that appear perfectly fine on Sunday afternoon can be totally defoliated by Wednesday afternoon.


Be alert for signs of leaf skeletonization caused by the young caterpillars. Infestations are most common in late summer and early fall. Early detection and control of young larvae can prevent serious defoliation injury. If you find only small numbers of caterpillars, remove them by hand. If you choose chemical controls, select products that contain active ingredients: permethrin, bifenthrin, carbaryl, acephate, cyfluthrin, cyhalothrin, Bts, or spinosad.