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Tomato
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â ModerateTarget-like concentric brown rings on lower leaves ïŋ― the classic sign of early blight.
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Fungal
Early Blight on Tomato Leaves
Commonly affects: Solanum lycopersicum (Tomato)
Dark brown spots with concentric rings, resembling a target or bullseye, appear on older, lower leaves first. A yellow halo often surrounds each spot, and severely affected leaves yellow entirely and drop.
Potential Causes
- 1Alternaria solani fungus, which overwinters in soil and plant debris
- 2Warm, humid weather with extended periods of leaf wetness
- 3Splashing water from rain or overhead irrigation spreading spores from soil onto lower leaves
- 4Stressed or nutrient-deficient plants being more susceptible
Solution Steps
- 1Remove and destroy affected lower leaves as soon as symptoms appear, rather than composting them.
- 2Mulch around the base of the plant to reduce soil splash onto foliage.
- 3Water at the base only, and avoid overhead irrigation that wets the leaves.
- 4Apply a copper-based or chlorothalonil fungicide preventively if early blight is a recurring problem in your garden.
Prevention Tip
Mulch heavily around tomato plants and always water at the base ïŋ― most early blight infections start with soil-borne spores splashing onto the lowest leaves.
