How Botrytis fungus got on my plants?

Bud rot is spread to plants by dusty gray spores, usually in wind or water. Most common ways Bud rot fungus spores get to plants is Wind and Rain Water. If your plants are never exposed to these spores, they will never get bud rot.

Unfortunately the spores can easily be carried to your plant by a breeze, rain, from contact with animals, or even by clones from another grow room. Dormant spores can survive in many conditions only to affect your crops another time!

But... it's not so bad. The fungus will never germinate if you take good care of your buds. And in any case, your plant needs a “wound” of some sort for the spores to take residence in your buds.

Possible wounds that can let Bud Rot fungus in include cracks in the stem from wind or over-training, damage from caterpillars, snails, worms, white powdery mildew, other pests and larva, or any other type of injury or weak point can the the point of entry for bud rot spores into the plant.

Bud Rot needs cool, wet conditions and stagnant air to thrive. What triggers spores to grow into a full-blown case of bud rot?

Cool temperatures (~60-70°F or 15-20°C) are ideal for spore germination

Wet Buds - Rainy weather, especially if it lasts for days in a row

High humidity - Any situation where buds remain wet for several continuous hours

Bad Air circulation - Lack of wind or air circulation over the top o through the inside the plant

Very leafy plants (which tend to collect water in between leaves, and prevent air circulation through the plant)

Big Colas - Massive, dense colas have nice wet conditions on the inside which don’t get exposed to any air. This makes them a prime target for Botrytis bud rot.