Why Your Basil Leaves Are Turning Yellow
Yellow basil leaves come from overwatering, cold, nutrient deficiency, or downy mildew. Check soil moisture and temperature first.
Basil is tropical. Most problems come from treating it like a temperate plant.
The 4 Causes
| Sign | Cause | Fix |
|---|---|---|
| Wet soil, droopy | Overwatering | Let dry |
| Below 60°F | Cold | Move to warmth |
| Old leaves first | Nutrient deficiency | Fertilize 1/4 strength |
| Yellow with dark spots | Downy mildew | No cure. Remove. |
What to Do
- Check soil. Wet → let dry.
- Check temperature. Below 60°F → move.
- Check leaves. Dark spots → downy mildew.
- Fertilize at 1/4 strength if none of the above.
Common Questions
Will yellow leaves turn green? No. But new growth will be.
Should I remove yellow leaves? Yes. They won’t recover.
Why only bottom leaves? Nutrient deficiency or light.
Can basil recover? Yes, if you fix the cause.
Is it downy mildew? Yellow leaves with dark spots, gray fuzz underneath.
How do I prevent it? Water from bottom. Keep warm. Airflow.