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Preventing Powdery Mildew on Pumpkins: Sprays Over Companion Plants

Companion planting does not reliably prevent powdery mildew. The disease is fungal, spread by spores, not insects.

Effective Organic Spray

Mix 1 tablespoon baking soda + 1 gallon water + 1 teaspoon horticultural oil or dish soap. Spray weekly, covering both leaf surfaces, starting at first sign or preventatively in humid weather.

Cultural Controls

Full sun, wide spacing.
Drip irrigation; avoid wetting leaves.
Remove infected leaves promptly.
Choose resistant varieties (e.g., 'Magic Lantern', 'Gladiator').

Sprays + culture = best defense.

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