Root rot and soggy roots
Root rot is what happens when roots sit in wet, airless mix for too long: fine roots die, then organisms that thrive in wet mix finish the damage. Above the soil it often looks like drought — yellowing, wilting, leaf drop — because the damaged roots can no longer supply the leaves.
The confusing part is that an overwatered plant looks thirsty, and watering it again is exactly what worsens the rot. The check that settles it is the roots themselves: healthy roots are pale and firm; rotting roots are brown to black, soft, and may smell bad. This page covers roots and underground storage organs (bulbs, tubers) rotting in wet mix; seeds rotting before they emerge and fruit rotting are different problems, not covered here.
General beginner information only — not a substitute for advice from your local agricultural extension service. For edible plants, use only a product that is labelled for that particular edible crop, for indoor use, and follow any harvest interval on its label; try non-chemical steps first, and never use a product that is not labelled for indoor use on that plant.
Checklist to diagnose
- Is the mix still wet days after watering, and does the pot stay heavy?
- Does the plant wilt even though the mix is wet?
- Is there a sour smell from the mix, or mould or algae on the surface?
- Lift the plant: are roots pale and firm, or brown to black, soft, and foul-smelling?
- Is the pot oversized for the roots, without drainage holes, or standing in water?
Rescue steps
- Stop watering immediately and let the pot drain fully; empty the saucer and keep it empty.
- Slide the plant out and inspect the roots. If most roots are still pale and firm, the fix is mostly patience: fresh air, drainage, and waiting for the mix to dry at check depth before watering again.
- If some roots are soft and dark, trim them back to firm tissue with clean, sharp scissors, cleaning the blades between plants, and repot into fresh, free-draining mix in a pot with drainage holes that fits the remaining roots — not a larger one.
- Discard the old mix and clean the pot before reuse; do not reuse mix from a rotted plant.
- After repotting, water once to settle the mix, let it drain completely, and then wait until the mix has dried at check depth before watering again. Watch for new growth, not for old leaves recovering.
When to give up
- The crown or stem base is soft and collapsing and almost no firm roots remain.
- No new growth appears after repotting into fresh mix and steady care — take a healthy cutting first if the species allows it, before discarding the plant.
Plants on this site
These plant guides on this site already mention this problem: