Know the Pests You Have Before You Try To Kill Them

Azaleas are popular in Alabama. You want to keep them healthy. Therefore, when you have a pest problem, make sure you know what problem you're dealing with before you buy a pesticide.

Plants that appear yellow, covered with black, sooty mold are probably infected with azalea bark scales. The crawlers hatch in late April to May and are found in the crotches of limbs and look like white, waxy masses. Use a pesticide when you can see the crawlers. Prune out dead or dying infested plants parts.

Full-grown azalea caterpillars are 1/4- to 1/2-inch long and are red to brown with white and yellow stripes. Chemicals will only kill small caterpillars. The rest must be removed by hand.

Azalea lace bugs are 1/8 inch long with lacy wings. They are usually found on the underside of leaves where they suck out plant juices.

Yellow caterpillars up to 1/2 inch long are called azalea leafminers. These pests cause brown blisters within the leaves. As they grow, insects come out of the leaf, roll up in the leaf's edge and feed on the leaf surface. Leaves then turn yellow and fall off.

Spidermites suck plant juices, causing leaves to drop. Spidermites are smaller than the head of a pin. Insecticidal soaps are helpful in controlling early-season mite population. Be sure to alternate chemical treatments to avoid resistance to the pests.

Oval-shaped holes found on azalea leaves are probably due to cranberry rootworm beetles. These shiny black bugs feed at night and hide during the day. To help control them, remove all ground litter and weeds from the area and reduce shade where possible. Use chemical treatments late in the day and repeat once or twice a week.