Diagnose fast
Yellowing starts on older leaves; pot feels heavy for days; core soil smells sour. Unpot: healthy roots are firm and pale; rot is brown/black and mushy.
Rescue steps
- Rinse roots; prune to firm, pale tissue.
- Repot in a fresh, airy mix (base + perlite/pumice + bark).
- Water lightly once; let the root zone re-oxygenate before the next drink.
- Increase light and airflow to normalize dry-down.
Prevention
Match mix to light; use pots with drainage; water in the morning and avoid saucer pooling.