1. Overwatering and poor drainage
Likelihood: HighYellowing that starts on older, lower basil leaves with limp stems usually means roots sit in soggy soil. Herbs grown near thirsty crops like peppers in beds often get watered more than they tolerate.
Identification
- remove_circle_outlineLower leaves yellow first, then soften, while newest top growth stays light green
- remove_circle_outlineSoil feels wet more than two inches down even several days after watering
- remove_circle_outlineContainer or bed has no clear drainage holes or water pools around basil stems
- remove_circle_outlineRoots appear tan or brown and smell sour when you gently dig near the crown
The Fix
- 1Check soil moisture two inches deep before watering and note how long it stays wet afterward.
- 2Skip watering until the top two inches feel dry, then water slowly until excess drains from holes.
- 3Improve drainage by loosening soil around plants and mixing in coarse compost or perlite lightly.
- 4If in pots, repot into fresh, well‑drained mix and a container with several open drain holes.
- 5Going forward, water basil only when the top one to two inches dry, never on a fixed schedule.