Does Rain Affect Marijuana Buds?

Does rain lessen the potency of buds? Can you shake marijuana plants post-rain to ward off mold? Is there a surefire way to avoid mold?

Rained-on buds face two major issues. The first issue is that the glands can be knocked off by wind and rain. Occasionally, only the gland heads can fall off, but these have most of the THC. This will occur as the buds start to reach maturity. Debris from the rain and wind can also be knocked onto the surfaces where they are then caught up in the adhesive glands.

A second (and indirect) issue with the rain is that the moisture promotes fungus and mold growth. The tight buds can take in drops of rain that remain there indefinitely. The dark, moist, and acidic area promotes perfect conditions for the growth of mold. You can keep mold from growing on the buds in a number of ways. Mold likes environments that are acidic, but stays away from alkaline ones. You can make the pH more alkaline by spraying it with water adjusted to around pH 8. You can do this with pH Up or potassium bicarbonate. Mold will not infect the plants until rain washes these products away. Alkaline water is ideal because it does not leave any toxic remainder and will not harm the marijuana plant. Gently shake the buds to remove any of the alkaline water from the surface.


Go Robert. He is the first person I have heard tell people to use higher pH water sprays.
The mad scientist is right on. I thought that was my secret.
Yes you can shake the plants to rid them of any water on the surface, but that only gets to the surface. The main problem from heavy rain is it beats the hell out of the buds. One of mother natures tricks to release seeds.
pH adjusted spraying to just the buds will help prevent mold, some good sunny days will do wonders.
Again this is another reason I grow indoors, I am mother nature.


PS I could have been a d$$k, and told you the best way to handle this is to take a hair drier out and slowly dry the buds when it rains. That would have been funny. Just imagine the sight. LOL


hey a hair drier might seem silly but during a wet fall ill go out with a leaf blower to dry out a full plant or a gas powered air compressor with air nozzle to (very carefully) spot dry inside the big colas. it definitely work but theres no price for a happy healthy lady, especially in areas where you might not harvest til November. spot drying also gives you a chance to see inside the colas to catch mold before it turns to rot. def have to try to ph water spray though. i thought all moisture was bad moisture.


didnt see the age of the post. whoops.

Better late than never mate :+1::kangaroo:

How often do you spray the buds with ph8 to protect from rain?

Hello, thanks for this community and support. I live in South Florida, excellent place for growing sun is so strong everything grows so fast and year long its so easy. I had a bad ending to couple plants grown during humid/rainy season. I am wondering if anyone can help me so can fix this going forward. These 2 plants posted, were green, and purple stem, beautiful healthy. I am not sure if this is bud rot, or I know the bigger one was left out at night with a rain storm, was green the day before, then went out and completely brown, bottom to top. stem and buds. I am not sure if I left the buds on too long, or or if bud rot, or just the rain was too much. The last pic is basically what the buds looked like a day or two before I saw this “browning”. How close is this to clip? I do not want this to happen to that plant, feel like I should of just cut my 2 plants but the white crystals were still there, no amber crystals, and the hairs were still turned out, not in. Any better identifiers when ready? Please help as I have many babies growing and want to get this right from September-June in Florida not much rain and sun all day. Thanks crew and assistance appreciated.