Plant guide:🌿 Basil
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⚠ ModerateSudden blackened patches after a cold night � basil is highly sensitive to chill injury below 10�C.
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Leaves
Basil Leaves Turning Black
Commonly affects: Ocimum basilicum (Basil)
Leaves develop dark, blackened patches or turn black entirely, often appearing suddenly after a cold night or exposure to a chilly draft. Affected tissue feels limp and doesn't recover once blackened.
Potential Causes
- 1Cold damage from temperatures below 10�C, since basil is highly sensitive to chill injury
- 2Sudden exposure to a cold draft, such as near an air conditioning vent or an open window
- 3Refrigerating fresh-cut basil, which causes similar blackening in harvested stems
Solution Steps
- 1Remove blackened leaves, since the damaged tissue won't recover and can become an entry point for rot.
- 2Move the plant to a warmer location away from cold drafts or windows, keeping it above 15�C.
- 3If new growth continues to emerge green and healthy, the plant will typically recover from an isolated cold event.
- 4Store harvested basil at room temperature in a glass of water rather than in the refrigerator.
Prevention Tip
Never refrigerate fresh basil, and keep growing plants away from cold windowsills or air conditioning drafts � basil is one of the most cold-sensitive common herbs.
