By Nora | April 1, 2021

There are many fungi or moss that may live in the outside of grow bags where your houseplants are growing. Most are not harmful to the plant itself, but they are unattractive. They range from simple mold or mildew to small mushrooms growing next to your plants. Controlling fungus in grow bags begins before you even place it in the container. Once it is in the container and infected, it is more difficult to eradicate, though it can still be controlled.

Mold proliferates in dark and damp environments. If you notice mold or fungus grew out your fabric bags, no need to worry. They can be removed and controlled. And most of them are even beneficial to plants. Moss is good for potted plants because it absorbs and retains water and nutrients, which helps plants grow. Potted plants lose valuable nutrients when their soil is dry. Using moss helps the soil to retain water and nutrients close to the plant’s roots.

The exteriors of these containers can be cleaned while the pots are still full. Fill a small basin with a solution of baking soda or vinegar mixed with water. Use a soft-bristled scrub brush to lightly scrub the pot, removing build up or moss. Then let the container air dry.


There are several methods to prevent mold in grow bags soil to some extent.

  • Avoid overwatering plants. Mold thrives in moist conditions,so too much water will help mold spores to develop. As a rule of thumb, you should water your plants once the top 2 inches or ¼ of the total soil volume is dry.
  • Remove debris (such as dead leaves) from the soil and wipe off dust or dirt from the leaves Leaving organic debris on the soil can provide a better environment for mold to grow. Don’t forget to trim dead parts of your plant, as well.
  • Provide plenty of light and ventilation to your plants. Sunlight or artificial light is essentialnot only for your plant’s growth but also for repelling mold. A source of ventilation, such as a fan on low setting, allows airborne particles to circulate around the plant freely.


  • Rebecca

    I’ve gotten extremely sick. I’ve been eating a lot of vegetable everyday from my canvas organic grow bags. Severe mold reaction. Did not find this out til a few days ago. Quit eating them and having slight improvement but not much. Do you know what could be wrong? I’m very concerned and have all the symptoms of mold toxicity. I live on the Puget sound. Thank you

  • Reda

    Hi, I have 3 canvas style grow bags. 1 black 1 green and 1 tan in color. The plants are growing beautiful and the veggies too. But the bottoms of the grow bags have dark greenish mold or algae looking stuff from bottom up to 6 or 7 inches up . My concern is is this dangerous to the roots, plants or veggies? Will they be safe to eat?

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