Common Azalea Pest Causes Lackluster Blooms

The azalea are blooming around the Main Line and their bright magenta, red and white flowers are hard to miss. Although this popular landscape plant is a relatively low maintenance shrub, there is one tiny pest that may be preventing your bushes from standing out quite as brightly as your neighbors.

The culprit? Lace Bug. This fly-like insect deposits its eggs on (and partially inside) the underside of the Azalea leaf. The eggs hatch into nymphs and become adults in just 30-40 days. Due to the relatively short lifecycle, they can multiply quickly and have several generations per season.

The lace bug is a piercing, sucking insect, which means it uses its mouth part to latch onto the plant material and suck the plant juices out of the leaves. This causes the leaves to turn yellow and fall off. We all know healthy foliage is crucial for a plant to survive! Overtime, lace bug will skeletonize and defoliate your plant, severely weakening it and making it more prone to secondary stressors like drought. Luckily, lace bug is relatively easy to control once it has been identified on your property and your azalea should make a full recovery if the case isn’t too severe!

Although lace bug most commonly affects Azalea in our area, this insect has been found on other plants as well. This is because different lace bug species have different host plant preferences. We have 28 different documented species of lace bug here in Pennsylvania, and some prefer the taste of Hawthorne, Oak, Black Walnut, Crab Apple and Sycamore trees, to name just a few.

Keep an eye out for these signs of lace bug damage in your landscape:

1. Leaves are yellowing and falling off. The plant may appear defoliated or bald in severe infestations.

2. Leaves have dark brown or black spots and a stick, powdery looking substance coating the leaves. There is an overall dirty appearance to the shrub.

3. Lackluster blooms because the plant has been weakened by a loss of leaves and stress from fighting off the lace bug.

If you are unsure if you have lace bug, reach out to us and we will complete a complete landscape evaluation for insects, diseases and other common landscape pests. If you think you have lace bug, mid-May to early June is the ideal time for treatment.