University of Florida

Powdery Mildew

Powdery mildew is a serious fungal disease that attacks a wide range of plants, from squash to roses. Crapemyrtles are especially susceptible. The symptoms are unmistakable: spots or patches of white powder, usually on the leaves.

These spots quickly enlarge, turning into a dusty white or gray coating. The symptoms usually appear late in the growing season.

Like all fungi, powdery mildew favors moist conditions and will thrive in humid weather, crowded plantings, and shade.

Damage to infected plants can include the stunting of leaves, buds, and fruit. Leaves may yellow and drop and the plant will suffer as it loses nutrients to the fungus.

To treat powdery mildew, spray infected plants with a fungicide labeled specifically for this disease. As always, follow all label instructions.

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