How to Identify and Fix Root Rot?

HomeProblemsDiseaseHow to Identify and Fix Root Rot?



Root rot is a fungal disease that targets plant roots, compromising their ability to absorb water and nutrients. This impediment leads to visible symptoms such as wilting, yellowing, and, in severe cases, plant death.

What is Root Rot?

Root rot is a condition caused by various fungi, including Phytophthora and Fusarium, thriving in excessively moist soil. These pathogens attack a plant’s root system, hindering its functionality.

What Does Root Rot Look Like?

Root rot is easiest to identify by the color of the roots. Healthy roots appear firm, whitish, or cream-colored. Unhealthy roots appear dark brown, black, mushy, fall apart, or smell like decay. Other symptoms of root rot:

  • A large number of yellowing or smaller, pale-colored leaves
  • A lot of leaves wilting or falling off the plant (unseasonably)
  • Brown splotches on leaves
  • Stunted growth
  • The rapid decline of the plant

How to Fix Root Rot?

Once established, root rot is hard to treat. The best you can do is remove the parts of the plant that are dying (including the roots) and provide it with fresh soil. If the root rot is widespread and has affected most of the plant’s roots and foliage, the plant may be beyond saving. However, if the plant has any healthy roots left, it may be possible to rehabilitate it using the following steps.

  • Remove the plant from its pot and gently shake off as much soil as possible from the roots.
  • Cut off any roots that are brown, black, mushy, or smell bad. Use a sharp and clean knife or scissors to avoid spreading any infection.
  • Rinse the remaining roots with clean water to remove any dirt or fungus spores.
  • Repot the plant in a new pot with fresh, well-draining potting mix. Make sure the pot has drainage holes and avoid using any saucers or trays that can collect water.
  • Water the plant lightly and keep it in a bright but indirect light location. Avoid fertilizing until you see new growth.
  • Monitor the plant for any signs of improvement or deterioration. If the plant does not recover within a few weeks, it may be too late to save it.

How does Root Rot Spread?

Root rot can spread from one plant to another through contaminated soil, water, tools, or pots. It can also spread through airborne spores or insects that feed on infected roots. To prevent root rot from spreading, you should:

  • Isolate any plants that show signs of root rot from healthy ones.
  • Sterilize any tools or pots that have been in contact with infected plants before using them again.
  • Avoid reusing any soil that has been infected with root rot.
  • Dispose of any infected plant material in a sealed bag or bin away from your garden or compost pile.
  • Use clean water to water your plants and avoid splashing water on the leaves or stems.
  • Control any pests that can transmit root rot, such as fungus gnats, aphids, or nematodes.

What Causes Root Rot?

Root rot is caused by prolonged exposure to wet soil conditions and has two sources.

First, overwatered conditions can starve a plant’s roots of oxygen, which causes them to rot and die. This rot can spread to all of the roots quickly and may persist even after the soil conditions have been corrected.

The second source of root rot is harmful fungi in the soil that thrive once exposed to wet soil conditions. Two main types of soil fungi can lead to root rot—fusarium and pythium.

  • Fusarium is a common soil fungus that thrives on dead or dying plant tissues
  • Pythium is a bacterial organism commonly transmitted by fungus gnats (which also thrive in consistently moist soil conditions).

How to Prevent Root Rot?

The best way to prevent root rot is to avoid overwatering your plants. Here are some tips to help you water your plants properly:

  • Choose a well-draining potting mix that suits your plant’s needs. To improve drainage, you can add perlite, vermiculite, sand, or gravel.
  • Choose a pot that has enough drainage holes and is the right size for your plant. Avoid pots that are too big, too small, or glazed.
  • Water your plants only when the top inch of the soil feels dry to the touch. Use your finger or a moisture meter to check the soil moisture level.
  • Water your plants thoroughly until water runs out of the drainage holes. Do not let the pot sit in water or use any saucers or trays that can collect water.
  • Water your plants in the morning or early afternoon to allow the soil to dry out before nightfall.
  • Adjust your watering frequency according to the season, weather, and plant’s growth stage. Water less in winter, more in summer, and more when the plant is actively growing.

Other ways to prevent root rot are:

  • Use good quality soil or compost that is free of pathogens and pests.
  • Test your soil pH and amend it if necessary to suit your plant’s preferences.
  • Fertilize your plants sparingly and according to the label instructions. Avoid using too much nitrogen or salt-based fertilizers.
  • Provide adequate air circulation around your plants by pruning, spacing, or ventilating them.
  • Reduce stress on your plants by acclimating them to new conditions, repotting them when needed, and protecting them from extreme temperatures or sunburn.

Types of Plants Affected

Root rot can affect almost any type of plant, but some are more susceptible than others. Plants in drier environments, such as cacti and succulents, can be overwatered more easily than happy plants in moist environments, like ferns or clothes. Some plants that are prone to root rot are:

  • African violets
  • Azaleas
  • Begonias
  • Cacti and succulents
  • Citrus trees
  • Ficus trees
  • Orchids
  • Palms
  • Philodendrons
  • Poinsettias
  • Tomatoes
  • Zucchini


Can root rot be cured?

Root rot can be cured if it is detected early and treated promptly. However, if the root rot is severe and has affected most of the plant’s roots and foliage, the plant may be beyond saving.

How do you get rid of root rot fungus?

The best way to get rid of root rot fungus is to remove any infected roots and soil from the plant and repot it in a fresh, well-draining potting mix.

Can hydrogen peroxide kill root rot?

Hydrogen peroxide can kill root rot by supplying oxygen to the roots and killing any fungus or bacteria present. However, hydrogen peroxide can also damage healthy roots if used too often or in high concentrations. A safe way to use hydrogen peroxide is to dilute it with water (1 part hydrogen peroxide to 3 parts water) and water your plant with it once a month.

Does cinnamon kill root rot?

Cinnamon can kill root rot by acting as a natural antifungal agent. You can sprinkle some cinnamon powder on the cut ends of the roots before repotting your plant.

How long does it take for a plant to recover from root rot?

The recovery time for a plant with root rot depends on how severe the infection was and how well you treated it. Generally, it can take anywhere from a few weeks to a few months for a plant to recover from root rot.

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