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Gray mold is a very common fungal disease that cannabis growers deal with. (Botrytis) It is able to germinate on plants that have moisture on them, and only when temperatures are in the 55-70 degrees Fahrenheit (13-21 degrees Celsius) range.

The areas on the plants that are not receiving as much light are usually the parts where mold first appears. During the flowering period, gray mold can spread to the flowering stalks and buds and do severe damage to the plants.

Marijuana mold can spread throughout seedlings and on seeds on male plants and cause them to die. Mold will begin white in color but will turn to a brown or gray as it progresses.

How To Prevent and Control Marijuana Mold

-Remove dead leaves from the plants

-Keep moisture off the plants when the lights go out

-Keep the humidity in the grow room below 50%

-Water the plants during the daytime so they have 4 to 5 hours of time to dry before dark

-Keep the temperature in the grow room above 70 degrees Fahrenheit.

-If using CO2, only run it during the daylight hours

-Add a dehumidifier to the room to help keep the moisture level down

-Remove the carpet and trash in the room where the spores could be living


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-Add an oscillating fan to the grow room so the air circulates and moves through the plants and grow medium

-Wash the walls and ceiling with a bleach solution

-Throw away and remove from the room any dead leaves from the plants

-If growing outdoors, cover the ground around the plants with landscape cloth to prevent the growth of weeds

 Items That Can Help to Get Rid of Mold

-Neem oil
-Fish oil
-Sesame oil
-Clove oil

If you see mold in your garden it is imperative to remove it immediately. 

Check each bud one by one. If you see mold make sure to cut it off the bud.  Wear gloves to protect your fingers.

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Moldy bud can cause problems when smoked and it is any cannabis grower’s responsibility to make sure nobody smokes bud with mold on it.

Marijuana mold can be a real problem for cannabis growers but can easily be prevented or taken care of.

To learn how to grow weed and all about cannabis diseases, and how to set up an entire hydroponic garden, go to Cannabis Training University.

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  • replica says:

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