Yellow leaves

Overview

Yellowing leaves almost always speak of imbalance. The distribution of the yellowing is the diagnostic key: uniform and diffuse means water or light; localized and vein-bound means nutrient deficiency; patchy means pathogen or pest.

In 70% of cases the cause is overwatering that suffocates roots and blocks nutrient uptake. The remaining 30% splits between nitrogen deficiency, low light and the natural ageing of basal leaves.

Differential diagnosis

Soggy soil + sour smell → root rot.

Interveinal yellowing → iron or magnesium deficiency.

Only bottom leaves yellowing and falling → natural ageing.

Stippling under the leaf → spider mites or thrips.

Natural remedies

Pause watering until the top 3 cm of substrate dry out.

Apply a banana peel tea (potassium) or nettle macerate (nitrogen), diluted 1:10, every 15 days for 2 months.

Treatments

If roots are compromised: pull the root ball, cut rotten roots with sterile shears, repot in dry sterile mix.

Feed with balanced NPK 20-20-20 at half strength for 3 consecutive weeks to stimulate recovery.

Prevention

Water only when needed — check with a finger or moisture meter. Pots with drainage, saucers emptied within 15 minutes.

Frequently asked questions