How to diagnose root rot in indoor plants?

Introduction

Root rot is a silent killer in indoor gardening — often hidden until it’s almost too late. The roots lose oxygen, turn mushy, and stop transporting water or nutrients. Luckily, you can catch it early if you know the signs beneath the soil and above the leaves.

1) Early leaf and stem symptoms

Yellowing that starts from the bottom up, wilting despite moist soil, and blackened stems near the base usually mean roots are decaying. Soft stems that collapse when pressed are a red flag.

2) Check root color and texture

Unpot your plant gently. Healthy roots are firm, flexible, and white to tan. Rotten roots appear brown to black, smell sour, and may slip their outer layer when touched — leaving a stringy core.

3) Soil condition & smell

A sour, stagnant odor or soggy compacted mix signals low oxygen. Dry on top but wet deep below means water is trapped — a common indoor issue in plastic pots or mixes lacking perlite.

4) Diagnosing causes

• Overwatering: watering too often or without drainage.
• Poor mix: dense soil holding water around roots.
• Low light: slows drying and lets pathogens multiply.

5) What to do next

If you catch root rot early, your plant can recover. Trim the damaged roots, repot in a fresh, airy mix, and reduce watering frequency. Increase airflow and light exposure for faster recovery.

Conclusion

Root rot diagnosis starts with your senses — look, smell, and feel. The sooner you unpot and inspect, the better your chances to save your plant from a full collapse.