On ornamentals, which steps are recommended when powdery mildew is observed?

• A. Ignore symptoms and continue regular watering.
• B. Confirm symptoms, improve air circulation and reduce humidity, and apply an approved fungicide if necessary.
• C. Remove affected plants and replace with mildew-resistant varieties.
• D. Prune heavily to remove all leaves.

Answer: (B)

Powdery mildew on ornamentals is best managed by a practical sequence: first confirm that what you’re seeing is indeed powdery mildew, so you’re treating the right problem. Then change the environment to make it harder for the fungus to thrive—improve air circulation by pruning or thinning crowded growth, space plants properly, and reduce leaf surface humidity by watering at the base and avoiding overhead wetting. If the disease continues after these cultural changes, treat with an approved fungicide following the label directions. This approach combines diagnostic accuracy, environmental suppression of the disease, and chemical control only when needed.

Ignoring symptoms allows the fungus to spread, and removing all infected plants or pruning heavily to remove every leaf is often impractical and can stress the plants further. A targeted, measured response preserves plant health while reducing disease pressure.