Root Rot in Herbs and Garden Plants: How to Detect and Fix It Early

Root rot is a silent killer. It starts underground, where you can’t see it, and by the time your plant’s leaves turn yellow or wilt, the damage is already serious. Whether you’re growing basil, rosemary, or tomatoes, root rot can destroy your plants quickly if not addressed.

Here’s how to identify, treat, and most importantly—prevent root rot in your garden or potted herbs.

What Is Root Rot?

Root rot is usually caused by:

• Overwatering, leading to oxygen-deprived soil

• Poor drainage in pots or compacted ground

• Fungal pathogens, especially Pythium, Phytophthora, and Rhizoctonia

These fungi thrive in wet conditions and attack plant roots, causing them to turn brown, mushy, and non-functional.

Symptoms of Root Rot

• Yellowing or drooping leaves

• Slowed or stunted growth

• Leaves falling off with no clear reason

• Foul smell coming from soil

• Roots that are soft, brown/black instead of firm and white

You may also notice the plant looks wilted even when the soil is moist—a clear red flag.

How to Treat Root Rot

1. Remove the Plant and Inspect the Roots
   Gently unpot the plant. Trim away all dark, mushy roots with clean scissors.

2. Rinse and Repot in Fresh Soil
   Wash the remaining healthy roots with lukewarm water. Use a well-draining, sterile potting mix.

3. Improve Drainage
   Use pots with proper drainage holes and never let water pool in the saucer.

4. Apply a Natural Fungicide (optional)
   Cinnamon powder or hydrogen peroxide solution (1 part peroxide to 3 parts water) can help disinfect roots and soil.

5. Reduce Watering
   Only water when the top inch of soil is dry—and adjust based on humidity, season, and plant type.

Long-Term Prevention Tips

• Use pots with drainage holes—no exceptions

• Add perlite, pumice, or coarse sand to your soil mix

• Water deeply but infrequently

• Don’t use the same soil repeatedly without refreshing or sterilizing

• Avoid compacting the soil surface—roots need air, not just water