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A weekly lesson in pest management for indoor gardeners. This week we will talk about how to combat botrytis cinerea, or bud rot.

What is botrytis cinerea (bud rot)

Botrytis cinerea, or grey mold is a type of fungus that favors damp, humid, and stagnant areas. It appears as a greyish - brown fluff that appears on your plants and their fruits or flowers. If allowed to continue the mold will slowly eat the plant and cause it to decay. Grey mold is a common fungus that impacts several different kinds of fruiting and flowering plants including cannabis.

What causes a Grey Mold breakout

The botrytis cinerea fungus, or grey mold, thrives in damp and humid environments. It can grow and spread in these conditions very quickly. Your environment can become too damp or humid if you have:

  • Lack of air circulation or movement in a closed space

  • Lack of fresh air intake in a closed space

  • Light is creating too much heat in a closed space

  • Too much water with too much heat causing too high a humidity in your garden

You can check to see if your garden has any of these conditions by asking yourself:

  1. Are my plants getting fresh air, or are they inclosed in an area for 12 - 24hrs at a time?

  2. Are my plants getting circulation of air, or are they inclosed in an area where the air is still and not moving for 12 - 24hrs at a time?

  3. What is the temperature inside my grow tent or where my garden is and is it to hot?

  4. What is the humidity level inside my grow tent or where my garden is, and is it to high?

Damage caused by Grey Mold

Grey Mold, or Botrytis cinerea is a necrotrophic fungus, which means it feeds on the dying tissue of the organism it has attached itself to. Once the conditions are right, Grey Mold gets to work breaking down tissue and slowly eating it. If left untreated, the Mold will spread and kill more and more of your plant. The Mold also has the ability to spread from one plant to another, leading to an infection of an entire garden.

Get rid of Botrytis cinerea or Grey Mold Checklist

  • Trimmers to cut off the moldy parts

  • Trash bags to safely dispose of the trimmed parts

  • Hygrometer to measure humidity

  • Thermometer to measure temperature

  • Possibly a better circulation system

  • Possibly more fans

  • Possibly a dimmable light to lower the light output and temperature in the tent

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