By Canopy Team on September 10, 2021
Powdery Mildew is a group of diseases caused by fungi that infect leaves, buds, flowers and/or stems. First appearing as small, white or gray, circular patches on plant tissue, it spreads rapidly to form powdery areas of fungus. In addition to white or powdery substance on leaves, some curling or wilting may happen as well.
Each species of powdery mildew only infects a small variety of plants, but unfortunately, there are over 11,000 types. Powdery Mildew is commonly seen on trees such as London Plane (Platanus x acerifolia), Crape Myrtle (Lagerstromeia spp.), and Valley Oak (Quercus lobata).
Powdery Mildew rarely causes the death of a tree, however, it can cause some dwarfing, discoloration, and even dieback (see picture on right). Although it’s mostly an eyesore, it should be treated, because it can cause stress and other issues. New growth may be stunted, and blossoms may fail to set fruit or may produce fruit covered with fungus.
There are a few solutions.
Source: Missouri Botanical Garden