Plant guide:🍅 Tomato
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⚠ ModerateA dry, dusty white coating on upper leaf surfaces — tomato powdery mildew can spread even without high humidity.
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Fungal
Powdery Mildew on Tomato Leaves
Commonly affects: Solanum lycopersicum (Tomato)
A white to grey powdery coating spreads across the upper leaf surface, typically starting on older leaves. Unlike tomato-specific leaf mold, this coating is dry and dusty, not velvety, and can occur even in relatively dry conditions.
Potential Causes
- 1Leveillula taurica or Oidium species fungi, which — unlike most powdery mildews — can infect even in low humidity
- 2Dense planting restricting airflow between plants
- 3Stressed plants (drought, heat) showing increased susceptibility
Solution Steps
- 1Remove heavily affected leaves and dispose of them away from the growing area.
- 2Improve airflow by spacing plants and removing excess lower foliage.
- 3Apply a sulphur-based or potassium bicarbonate fungicide at first signs of white patches.
- 4Keep plants consistently watered to reduce drought-stress susceptibility.
Prevention Tip
Unlike many powdery mildews, tomato's version doesn't need high humidity to spread — good airflow and healthy, unstressed plants are the best defence regardless of weather.
