Aren’t these roots in the picture beautiful?  We wish we lived in a world where all roots looked this way, but sadly we don’t.  Because we live in the real world, houseplants, trees, plants, or shrubs are often over watered; their leaves start to get dull, turn yellow and the plants will show other signs of stress.  When this happens to a plant, it might be suffering from root rot.

Causes of Root Rot

  • Root Rot can be caused by prolonged exposure to over watered conditions that cause some of the roots to die back due to a lack of oxygen.  As they die, they decay and rot away.  The rot can spread to healthier roots killing them too, whether or not the soil conditions are corrected.
  • Root rot can also be the result of a fungus in the soil.  The fungus can be dormant in the soil for years and suddenly come to life when a plant is over watered.  The root rot fungus attacks the roots and causes them to die and rot away.

Signs of Root Rot

Symptoms of root rot include leaves that are smaller than usual that may wilt and turn yellow or brown.  The plant or tree begins to decline gradually or quickly for no obvious reason.  Brown or blackened and damaged areas are visible on crowns and roots.  Root rot on trees is indicated by white mats of fungi and dark brown fungal strands found on the roots or growing between the bark and wood.

If the plant is slowly wilting and the leaves are turning yellow for seemingly unknown reasons, check the roots.  Remove the plant from the soil and feel the roots.  The roots affected by root rot will look black or brown and feel mushy.  Affected roots can actually fall off the plant when touched.  Healthy roots may be white or pale, but will feel firm.

Getting Rid of Root Rot

It can be tough to get rid of root rot and many people feel it’s easier to just scrap the plant and start over.  However, there are proven techniques that can cure your plant of root rot problems.  To try and get rid of root rot successfully, a two pronged approach is your best path to success.  You will need to treat the plant’s roots directly and you will also need change the plant’s environment so that root rot no longer has a good place to grow.

If you don’t fix the environmental causes of root rot, then it will just keep coming back no matter what else you do.  Making it important to go through the list we’ve created and make sure you’re covering all your bases to prevent it from happening again.  It should be noted that affected roots will likely never recover, just like how discolored leaves on the plant will never recover.  Instead you should be looking for new, healthy white root growth.

Treatment & Prevention

  • Keep your grow area as clean as possible at all times to stop bacteria and fungus before they start.  Before you begin your grow, you should also clean all grow-related items to kill all bacteria and fungal spores.
  • Add a root treatment into the mix to help prevent and treat root-related plant diseases and help make nutrients readily available to the plant.  Dyna-RHIZ, a mixture of multiple mycorrhizal species will help create an unfriendly environment for undesirable bacteria and fungi.
  • If you have a hydroponic system, it’s best to change your reservoir water regularly in order to prevent any one type of bacteria from overgrowing the whole reservoir.  We recommend trying to change your water at least once a month.  There are however, many growers who change nutrient solutions in the reservoir weekly.
  • Changing your nutrient solution regularly will also help your plants get better access to nutrients and the roots of the plant love that 10-15 minutes where they get access to the oxygen in the air.  Be careful and ensure they never get dry though.
  • It is beneficial to try to get as much oxygen as possible dissolved in your water. This can be accomplished with an air pump and air stones for your hydroponic nutrient system.  The more bubbles and surface agitation, the better, as this dissolves more oxygen into the water.  Root rot cannot thrive in an oxygen-rich environment and your plants roots will love it.  Note that aeration of the nutrient solution not only adds O2 to your nutrients, it also adds CO2.  When carbon dioxide dissolves in water, if forms carbonic acid, a weak acid that will lower the pH of your nutrient solution.  Accordingly, you will need to pay closer attention to the pH of your nutrient solution when aerating the reservoir.
  • Ensure that the temperature of the water never gets warmer than a comfortable room temperature. Warm water holds much less dissolved oxygen than colder water and also provides the perfect environment for bacteria to grow.  The maximum recommended temperature for the water in your reservoir is around 72°F (22°C).  Trying to maintain water temps around 65°F – 68°F (18°C – 20°C) seems to be optimal for both plant growth and root rot prevention.
  • In a hydroponic system, ensure that any dead roots, dead leaves or other types of plant debris doesn’t get into the reservoir because they will provide a breeding ground for bad bacteria as they start rotting.
  • Don’t let any light get to your roots or reservoir water ever, as it provides heat and light which will promote the growth of bacteria.

It’s important to remember that your plant can recover from root rot when you catch the problem early enough.  Which is why it’s so critical to be vigilant for signs of root rot during your grows, especially when growing with hydroponics.