This is a tough time of year for many outdoor cannabis growers. As temperatures drop and days become shorter, plants begin to accumulate moisture, and many end up developing powdery mould or bud rot, which can have devastating effects on a cannabis crop.
Powdery mould is one of the most common forms of mould found on cannabis plants. It appears as dusty white spots on the leaves, and if left untreated may spread to the buds and cause bud rot.
Bud rot occurs when a fungus develops in the stem of cannabis plants and spreads to the buds. Bud rot appears as “dried out” or “dying buds” which are usually found on the colas, accompanied by yellowing leaves around the rotted bud.
It is always advisable to prevent mould in a cannabis garden, but sometimes Mother Nature doesn’t cooperate, it rains, and mould develops. If you find powdery mould on the leaves of your plant, the best treatment method is a baking soda spray. Mix 1 tsp. of baking soda to 1 Litre of water and use it as a foliar spray first thing in the morning. This will work to dry up the powdery mould, and the white spots should eventually disappear.
Bud rot can be a bit trickier to deal with, as it is hard to detect in its early stages since it occurs at the stem of the plant and spreads outwards. Most growers don’t know they have bud rot until they start to see the tops of their colas rot. If bud rot does occur, cut out the mouldy bud and ensure that there are no remaining signs of mould on the surrounding areas.
It is crucial to ensure that cannabis is mould-free at the time of harvest, as smoking mouldy bud can have serious health impacts. If you are unable to rid your plant of mould prior to harvest, toss your plant in the garbage, it is not worth the risk!