How to Identify and Prevent Growing mold on Cannabis

How to Identify and Prevent Growing mold on Cannabis

There are many options for what to do about mold in cannabis plants. Do you keep them, throw them away, or use them anyway? It is important to know the dangers of certain molds and how they could impact your products. You can get rid of the molds by using tissue culture and cannabis clones methods. Three times are you more likely to find mold on cannabis plants.

During the vegetative phase

Your plants will grow tall and lush if they have little airflow. The more vegetation plants have the higher their water emissions. Airflow is affected by the size of the growing area. This can lead to stagnant air pockets and is common in small growing spaces like tents.

The last few weeks in flowering

The mold-sensitivity of flowers increases in the last weeks of flowering. It is easier for colas to get infected if they are larger or denser. Mold can come in many colors. This stage of mold growth on cannabis is commonly called Botrytis or Bud Rot. Bud rot causes the leaves surrounding the cola to turn yellow or fall off, and the bud itself becomes discolored. It's crucial to assess your plant immediately if you notice any visual differences in one bud.

Drying and Curing

The drying and curing methods you use can affect the quality and appearance of your buds. They also have the potential to prevent or create mold. It is important to follow all steps and check your cannabis frequently. To release toxins and allow fresh air in, open jars at least once per day. Now that you are aware of when to look out for cannabis mold, let us get to the how-to's to prevent it.

Botrytis/Bud Rot

Botrytis is also known as gray mold, bud rot or a pathogenic fungal disease. It is one of the most prevalent fungi on marijuana plants. Botrytis can cause damage to the roots, stems and leaves of marijuana plants and can kill them in a matter of days.Botrytis is a disease that can be spread through wind and rainwater. It will germinate plants by inflicting an injury. You can prevent bud rot from occurring if your plant has been exposed.Identifying Bud Rot

  • You can detect bud rot early in stages if you see fluffy white growth on your buds.
  • Botrytis can be easily detected by changing the color and becoming dry.

Preventing Bud Rot

  • Move infested plants to an area outside where you can spray them to reduce their population.
  • Humidity – Control humidity levels by reducing it below 50%
  • Bee glue or propolis - Available online or in retail shops and can be used immediately.
  • Dispose of infected parts of your plant. You can create a safety margin by removing a small portion of the healthy.
  • Use a HEPA air filter unit to ventilate the growing area (MERV15 and higher recommended).
  • Horsetail - One ounce of powder makes one gallon of ready to spray solution.
  • Essential oils such as rosemary, thyme, black caraway, and lemongrass can be used to diffuse bud rot.
  • Silica – Can be used in soil as a strengthener, alkaline adjustor, and can easily be administered using a high-silica fertilizer.

Powdery Mildew

Powdery mildew usually affects older leaves first, and can cause some to become damaged or break.Although not the most serious fungus, powdery mildew can cause damage to buds and prevent safe consumption. These are some precautions you can take to prevent this fungus attacking your plants.Identifying Powdery Mildew

  • You may see small white dots on the stems and leaves during the early stages of powdery mildew.
  • The fungus will get denser as it progresses, covering the stem, leaves, and buds with thick white mildew.

Preventing Powdery Mold

  • Horsetail - One ounce of powder makes one gallon of ready to spray solution.
  • Bee glue or propolis - Available online or in retail shops and can be used immediately.
  • Capture and Remove - An MERV15-or higher HEPA air purifier will remove sub-microns, preventing Powdery Mildew
  • Trichoderma Harzianum is a soil-based preventative against powdery mildew


Fusarium, also known as filamentous fungi and parasites, lives in soil and feeds on plants, eventually infecting them and eventually killing them.Fusarium can cause wilt depending on the strain of marijuana. In others cases, it may cause root rot. Fusarium Root Rot can cause the roots to turn red and spread up the stem, leading to the plant swelling, breaking open, wilting, and eventually bursting.Fusarium can stay dormant in soil for many years. It is easily spread by water movement and contact with garden tools. Fusarium attacks can be fatal so it is important to get rid of all the Fusarium-infected materials, even seeds.Identifying Fusarium

  • The lower leaves will soon turn yellowish-brown from dark spots.
  • Leaves may wilt, but they will not fall off.
  • Your stems may droop.

Fusarium Prevention

  • You must immediately remove infected areas of the plant as soon as Fusarium is discovered.
  • You can move plants indoors or relocate your outdoor plants.
  • Bordo Mix – An organic fungicide mixture made up copper, sulfate, and slaked limestone and used for spraying
  • Grow room filtration systems: A highly efficient air cleaning system will ensure the purest air in your grow room. Recommended filters: MERV15 (95%) and MERV17(HEPA).

Penicillium, Aspergillus and Rhizopus Mold and Micro Organisms

Indoor and outdoor growers are both affected by mold and microorganisms. They can be very different in appearance and impact on people and animals. To protect patients and customers, it is best that growers understand and inspect plants at all stages of their growth. You must throw out any Aspergillus or Penicillium spores found on your plants. The spores of Aspergillus Penicillium, Rhizopus and Rhizopus fungus can survive almost any environment by drifting into the air. You can avoid these dangers by taking preventive measures early.Identification of Aspergillus and Penicillium

  • Aspergillus is a common mold that can be found indoors or outdoors. Aspergillus spores are generally dark green-black and cause an infection of the lungs. They can also be found in soil or buds.
  • Penicillium- Predominantly indoor mold. Light blue-green spores are common and can cause damage to crops as well as infecting and causing illness to both humans and pets.
  • Rhizopus- This spore produces gray-black spores that can infect humans under certain circumstances, such as when the immune system is compromised.

Preventing Aspergillus Penicillium, and Rhizopus

  • Hygrometer – Measures humidity in the air.
  • Fresh air - A dynamic air filter system can be used to ventilate your grow space and prevent mold and microorganisms contaminating it.
  • Silica gel packets - Keep moisture levels down.