Aroid Root Rot: Prevention and Treatment

By Marcus Williams · October 1, 2026

What Is Root Rot

Root rot is a fungal or bacterial infection that attacks plant roots, turning them brown, mushy, and foul-smelling. In aroids like Monstera, Philodendron, and Pothos, root rot is almost always caused by overwatering or poor drainage.

Identifying Root Rot Early

Yellowing leaves that do not improve with watering
Wilting despite moist soil
Dark, mushy roots when inspected
Foul smell from the soil
Sudden leaf drop

Immediate Treatment

Remove the plant from its pot and gently wash away old soil. Cut away all affected roots with sterilized scissors, leaving only firm, white or light-tan roots. Dip remaining roots in a 3% hydrogen peroxide solution for 30 seconds.

Repotting After Treatment

Use fresh, well-draining aroid mix: 40% potting soil, 30% orchid bark, 20% perlite, 10% worm castings. Choose a pot with drainage holes and only slightly larger than the root ball. Wait 3-5 days before watering to let cut roots callus.

Prevention Strategies

Water only when the top 2 inches of soil are dry. Use pots with drainage holes. Avoid letting plants sit in saucers of standing water. In winter, reduce watering frequency by half. Consider self-watering pots with moisture indicators.

The Science Behind It

Root rot pathogens like Pythium and Phytophthora thrive in waterlogged soil because they need water to swim and infect roots. Well-aerated soil creates an environment where these organisms cannot proliferate, which is why drainage is the single most important factor in prevention.