Root Rot in Banana Plants
Root rot is caused by soil-borne fungi (commonly Pythium and Phytophthora species) that attack banana roots in waterlogged conditions. It is preventable and, if caught early, treatable.
Symptoms
- Yellowing leaves despite adequate watering
- Drooping, wilting leaves
- Mushy, dark brown or black roots (healthy roots are white to light tan)
- Foul smell from the root zone
- Base of pseudostem feels soft or spongy
Causes
Overwatering, poor soil drainage, and heavy clay soil are the primary causes. Container plants with blocked drainage holes or sitting in saucers of water are also at risk. See Soil and pH.
Treatment
- Stop watering immediately
- If in a container, remove the plant, trim all rotted roots with sterilized shears, and repot in fresh, well-draining soil
- If in the ground, improve drainage by amending the soil or redirecting water flow away from the plant
- Apply a fungicide labeled for Pythium/Phytophthora if available
- Reduce watering frequency going forward — let the top 1-2 inches of soil dry before watering again (see Watering)
Prevention
Good drainage is the best prevention. Never plant bananas in low spots where water collects. In containers, ensure drainage holes are open and do not let pots sit in standing water. A well-draining soil mix is critical — see Soil and pH.