Root Rot in Garden Beds: Diagnosing and Treating Soil-Borne Fungal Disease

Plants Collapsing with White Fuzzy Roots? It's Root Rot

When multiple plants in the same area wilt, develop white fungal growth at the base, and smell musty, a soil-borne root rot pathogen (e.g., Pythium, Phytophthora, Rhizoctonia) is likely. Poor drainage, overwatering, or contaminated soil are common causes.

Immediate Actions

1. Remove affected plants and dispose of them (do not compost).
2. Inspect roots: Brown, mushy, easily stripped cortex = root rot.
3. Improve drainage: Amend soil with coarse sand, perlite, or compost; create raised beds.
4. Adjust watering: Water deeply but infrequently; allow top inches to dry.
5. Test soil pH and correct if extremely high or low.

Treatment Options

• Biological: Products containing Trichoderma, Bacillus, or mycorrhizae (e.g., RootShield, Actinovate) suppress pathogens.
• Chemical: Fungicides like mefenoxam (Subdue) or phosphonates (Aliette) as soil drenches—follow labels strictly.
• Solarization: Cover moist soil with clear plastic for 4–6 weeks in summer to heat-kill pathogens.

Prevention

• Use disease-free plants and sterile potting mix.
• Avoid moving soil from infected areas.
• Rotate plant families in beds.
• Maintain good air circulation and avoid overcrowding.

If the problem persists, send a soil/root sample to a diagnostic lab for precise pathogen identification.