Plant guide:🌿 Basil
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⚠ MinorPale, bleached patches on leaves suddenly exposed to intense sun � a hardening-off issue rather than disease.
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Light
Sunscald and Leaf Bleaching on Basil
Commonly affects: Ocimum basilicum (Basil)
Pale, bleached, or papery patches develop on leaves that were recently moved into much stronger direct sun than the plant was previously accustomed to, particularly after being hardened off too quickly.
Potential Causes
- 1Sudden transition from indoor or shaded growing conditions to intense direct outdoor sun
- 2Skipping or rushing the hardening-off process for seedlings started indoors
- 3An unexpected heatwave hitting plants not yet acclimated to intense light
Solution Steps
- 1Move the plant back to a slightly shadier spot, or provide temporary shade cloth during the hottest hours.
- 2Reintroduce increasing sun exposure gradually over 7�10 days rather than an abrupt full-sun placement.
- 3Remove severely bleached leaves, since they won't recover, but new growth should acclimate normally.
- 4Water consistently during the adjustment period, since a well-hydrated plant tolerates light stress better.
Prevention Tip
Harden off basil seedlings gradually over a week to 10 days when moving them from indoors to full outdoor sun, increasing direct light exposure a little more each day.
