Root Rot
What This Symptom May Mean
Root rot is a fungal condition that develops when roots sit in waterlogged soil for extended periods, depriving them of oxygen and allowing pathogens like Pythium and Phytophthora to thrive. Affected roots turn brown or black and become mushy, losing their ability to absorb water and nutrients. If caught early, the plant can often be saved by trimming damaged roots and repotting into fresh soil.
Common Causes
- 1Chronic overwatering keeping the soil constantly saturated
- 2Poor drainage from pots without drainage holes or compacted soil
- 3Using heavy, water-retentive soil mixes not suited to the plant species
- 4Oversized pots that hold more moisture than the root system can use
- 5Cool temperatures slowing evaporation and keeping soil wet for too long
How to Check
- ✓Gently remove the plant from its pot and inspect the roots — healthy roots are white or tan and firm
- ✓Smell the root ball: rotting roots produce a foul, musty odor
- ✓Look for dark brown or black roots that feel slimy or fall apart when touched
- ✓Check if the soil is consistently wet or waterlogged despite normal watering
- ✓Observe the foliage for yellowing, wilting despite moist soil, or a general decline in vigor
What to Try First
- →Remove the plant from its pot and trim all brown, mushy roots with sterilized scissors
- →Wash the remaining healthy roots under running water to remove fungal spores
- →Repot into a clean container with fresh, well-draining potting mix
- →Ensure the new pot has adequate drainage holes and is not oversized
- →Reduce watering frequency and only water when the top inch or two of soil is dry
- →Consider applying a fungicide drench to protect remaining roots during recovery
Plants Commonly Affected
Related Topics
Overwatering
Overwatering is the single most common cause of houseplant death. It occurs not just from giving too much water at once, but more often from watering too frequently before the soil has had a chance to dry out appropriately.
Well-Draining Soil
Well-draining soil allows excess water to flow through the pot quickly while still retaining enough moisture for roots to absorb. It is a critical factor in preventing root rot and maintaining healthy root systems for the vast majority of houseplants.
Repotting
Repotting is the process of moving a plant into a new container, typically with fresh soil, to give its roots more room to grow and to refresh the growing medium. It is one of the most impactful maintenance tasks a houseplant owner can perform.
Need more help with root rot?