Powdery mildew
White powdery coating on leaves, common in greenhouses and autumn.
Updated on 2026-07-17
Causes
Temperature swings, stagnant air, high night humidity.
Diagnosis
Powdery patches spreading across leaves.
Solutions
Baking soda + soap, or micronized sulfur on cool days.
Prevention
Ventilate, space plants, avoid wetting foliage in the evening.