Yellow leaves: check the causes before treating

A yellow leaf may be part of normal ageing or point to several growing problems. Start with observation and the roots; do not automatically apply fertiliser.

Distinguish an old leaf from a wider change

Note which leaves are affected and how quickly the change is progressing. Check new growth, stems and both sides of the foliage. Compare with earlier photos so you do not mistake a cultivar’s natural colour for a symptom.

Check in a useful order

1. Substrate moisture and any standing water in the cachepot.
2. Root condition if the plant stays waterlogged or is declining.
3. Visible pests, spots and localised damage.
4. Changes in light, cold or direct heat.
5. Repotting and fertilising history.

The watering guide and the guide to plant nutrient deficiencies explain the approach.

Address the observed cause

Adjust one condition at a time and monitor new growth. A change in colour alone does not prove a nutrient deficiency. If the problem persists, seek a documented horticultural diagnosis. For brown edges, read the guide to brown leaves. If light levels have changed, assess the setup and use suitable lighting only if the assessment supports it.

Editorial review: 3 October 2026 · TerraLED. Set up your equipment according to its instructions and the needs of the species.