We have chokeberry bushes about 5 years old and now about 10 feet high on the boundary of our backyard. Right now, they’re quite beautiful. But in each of the past five years, come early July, they lose about half their foliage and don't recover it. The loss looks natural in that leaves redden quickly, then drop while the remaining leaves look healthy. Any suggestions?
Chokeberry (Aronia) shrubs are susceptible to several different fungal diseases (leaf spots, rusts, mildew). These problems are common in Aronia plants and can lead to early leaf drop. In very wet years, like last season, the problems tend to be worse. Unless you are cultivating chokeberries for the edible fruit, we do not recommend any type of treatment. There is nothing curative for fungal diseases once the symptoms appear. Hope for drier weather this season. Pruning to thin the shrubs can improve air circulation and make them less susceptible to fungal infection.