Plant guide:ðą Mint
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â MinorScattered brown spots across mint leaves ïŋ― typically spread by splashing water in humid conditions.
ðĐš
Fungal
Leaf Spot on Mint
Commonly affects: Mentha spicata, Mentha piperita (Mint)
Small, circular brown or tan spots appear scattered across leaves, sometimes with a darker border. Spots may merge in severe cases, causing affected leaves to yellow and drop prematurely.
Potential Causes
- 1Septoria or other leaf-spot fungi spread by splashing water and humid conditions
- 2Overcrowded plantings limiting airflow between leaves
- 3Leaf debris left on the soil surface harbouring fungal spores over winter
Solution Steps
- 1Remove and destroy affected leaves promptly to reduce further spore spread.
- 2Clear fallen leaf debris from around the base of the patch, especially at the end of the growing season.
- 3Water at the base rather than overhead, and avoid working around wet foliage.
- 4Apply a copper-based fungicide if the problem recurs each season.
Prevention Tip
Keep the area around mint clear of fallen leaf debris, since many leaf-spot fungi overwinter there and reinfect new growth in spring.
