Common Encore Azalea Pests
If you've planted Encore Azaleas in your garden, you've probably already fallen for their biggest selling point. Unlike old-school azaleas that bloom once and disappear for the rest of the year, Encores rebloom in spring, summer, and fall. It's a lot of color for not a lot of effort.
But "low-maintenance" doesn't mean "maintenance-free." Even the toughest Encore varieties can attract a few unwelcome visitors if conditions tip in the pests' favor. The good news is that most azalea problems are preventable once you understand why they show up in the first place. Here's what to look for, what causes it, and how to keep your azaleas thriving.
The Usual Suspects
Azalea lace bugs are the number one pest to watch for. These tiny insects feed on the undersides of leaves, leaving behind pale yellow or bronze stippling on top and small dark specks (their excrement) underneath. The good news is that Encore Azaleas actually have a leg up here. A 2009 USDA study found eleven Encore varieties to be resistant to lace bug feeding, so newer Encores are naturally better equipped to fend them off than older azalea types.
Spider mites are another common culprit, especially during hot, dry stretches of summer. They suck sap from leaves, causing yellowing or bronzing, and in severe cases can lead to leaf drop and stunted growth.
Aphids tend to show up when the weather turns humid and plants are crowded too close together without good airflow. They cluster on stems and new growth.
Azalea caterpillars are a late-summer into fall problem. Left unchecked, they can chew through and defoliate an entire shrub.
Scale insects are less common but still worth checking for. Look for small waxy bumps along the stems.
How to Prevent Problems Before They Start
Plant in the right spot. Well-draining, acidic soil with about 4–6 hours of sun and some afternoon shade is the sweet spot for Encores.
Give plants room to breathe. Proper spacing between shrubs cuts down on the humidity and stagnant air that invite aphids and fungal issues.
Water at the base, not overhead. Overhead watering splashes fungal spores from leaf to leaf. Water early in the day so any moisture on the foliage dries out quickly.
Don't overdo the fertilizer. One slow-release application is usually plenty. More than that just makes your plant more attractive to pests.
Do a quick inspection every time you water. Catching a small infestation early is far easier than dealing with a full-blown one later. Don't forget to check the undersides of leaves, where lace bugs like to hide.
Clean up debris. Fallen leaves and spent flowers can harbor fungal spores through the winter, so raking them away helps protect next season's growth.
Bring in the beneficial insects. Ladybugs, lacewings, and parasitic wasps are natural predators of aphids and lace bug nymphs. A garden that welcomes them needs less spraying.
Start mild if you do see pests. A strong blast of water from the hose knocks aphids right off. For lace bugs or mites, insecticidal soap or neem oil applied to the undersides of leaves is usually enough to get things back under control.