Root rot symptoms: above and below the soil
| Where to look | What root rot looks like |
|---|---|
| Leaves | Yellowing on several leaves at once, wilting despite wet soil, dark or mushy blotches |
| Stems | Soft, brown or blackened at the soil line |
| Soil | Stays wet for a week or more; sour or swampy smell |
| Growth | Plant stalls — no new leaves during the growing season |
| Roots (the proof) | Brown/black, mushy, smelly; outer layer slides off leaving a thread. Healthy roots are firm, white or tan |
The above-soil symptoms are easy to mistake for thirst — a wilting plant tempts you to water more, which makes rot worse. If you’re unsure which side of the line you’re on, start with overwatering vs underwatering: how to tell.
What causes it
Root rot is what happens when roots sit in waterlogged, airless soil. Suffocating roots die, and opportunistic fungi and water moulds (Pythium, Phytophthora, Fusarium, Rhizoctonia) move in and spread through the root system. The triggers are almost always the same: watering on a schedule instead of by soil dryness, pots without drainage holes, dense water-retentive soil, or a pot far too big for the plant.
The rescue: unpot, inspect, trim, disinfect, repot
- Unpot immediately. Slide the plant out and gently crumble away the wet soil so you can see the whole root ball. Rinse the roots under lukewarm water.
- Inspect. Healthy roots are firm and pale; rotten ones are brown-black, soft and smell bad. Map how much is still alive.
- Trim ruthlessly. With clean, sharp scissors, cut every rotten root back to healthy tissue. If more than half the roots go, prune some foliage too, so the reduced root system isn’t supporting a full canopy.
- Disinfect. Wipe your scissors with 70% isopropyl alcohol between cuts. Wash the pot with hot, soapy water (or dilute bleach, then rinse well) — or use a new one. Never reuse the old soil.
- Repot. Use fresh, fast-draining mix (add perlite or bark) in a pot with drainage holes, sized just slightly larger than the trimmed root ball. Water lightly once, then not again until the top few centimetres are dry.
- Recover gently. Bright, indirect light; no fertilizer for 4–6 weeks; expect some sulking. New growth is your all-clear signal.
Plan B: propagate to save the plant
Even a plant that’s beyond rescue often has healthy tissue above the rot. Cut a stem section just below a node from firm, green growth, remove lower leaves, and root it in water or moist perlite. Pothos, philodendron, monstera and most vining aroids root readily this way; many succulents restart from a single healthy leaf. You lose the original root system but keep the plant.
Not sure it’s root rot? Get a second opinion in seconds.
Scan the plant with FloraCure and the AI weighs the symptoms — leaf pattern, discoloration, severity — and tells you whether you’re looking at rot, a watering issue or something else, with a confidence score and a treatment plan. Then set a watering reminder so the soil never sits soggy again.
Coming soon to Google Play →Prevent root rot for good
- Water by soil dryness, not by calendar — check with a finger to the second knuckle first.
- Only use pots with drainage holes, and empty the saucer after watering.
- Choose a chunky, well-aerated mix; pure dense potting soil holds too much water indoors.
- Size up pots by one increment only — a huge pot is a huge reservoir of wet soil.
- Water less in winter, when plants drink far more slowly. See how often to water a monstera for a seasonal example.
