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Treating Powdery Mildew on Potatoes

White powdery coating = powdery mildew (fungus). Dish soap + oil kills insects, not fungus. Use lime sulfur, copper fungicide, or fungicidal soap (e.g., Gardens Alive Soap Shield). Spray at first sign to prevent spread.

Prevention

Improve air circulation.
Avoid overhead watering.
Apply preventive sprays early.

Act fast — once widespread, control is difficult.

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