Killing mold on marijuana with alcohol

A question from a fellow grower:

I am having a problem with my outside plants
Black mold on spots on the limbs
One thing the plants are a little close.
I thinned out some leaves out…
I have been cleaning it with alcohol and
Q-tips. Is the a better way of killing the mold?

If you are going to go to the trouble of detailing each individual spot of mold with a q-tip, I’d use bicarbonate instead. Baking soda has extreme high ph. It will kill almost any mold/mildew/fungus. You can make solution, approximate 0.5% concentration when mixing 1 TBS per Gallon and keep this solution to dab on spots, much better than alcohol which could actually damage any trichomes it comes in contact with them. The bicarbonate solution can be rinsed off with pure water without any damage to trichomes, you can even mist a whole plant with this solution weekly, but you need to be careful it doesn’t get in the soil and you would want to rinse it off the plant the day before before a fresh application as you also don’t want it to continue to build up on the plant’s surfaces. It can cause a harsher smoke if you don’t get it all cleaned off with misting rinses of pure water after the mildew is gone, right before harvest. Rinse during the day with plenty of time to completely dry before dark.


I use 1/2 tsp baking soda per squirt bottle. Creates a PH too high for mold to live. You must be diligent in rinsing, but this will work.


Hey folks… ive been growing in Maine for years and when Sept comes around… it’s time to watch out for mold! -the best natural method I’ve found tht is amazing… and the plants love it… is a mix of milk, water and hydrogen peroxide. -Google search it and read up! - milk and peroxide are both also beneficial for the plant and roots. When I start to see mold appear… I start by soaking my plants with a foliar spray of it to deter more growth… but as a spot trearment… it kills it right away and doesn’t spread.

-happy growing!!

-and hybrid your strains! -create new, stronger and custom strains and name them!! :slight_smile: -don’t just grow only one strain over and over… it creates inbreeding, which extinction is the only result in the long run!


@bythesea this is the post I was referring to read the one from Macgyverstoner and latewood and try doing this if that fails I would cut cut that bud out and keep an eye on them
@WillyJ look at post above :+1: peace brother


Can you confirm that you’re talking about bud rot and not powdery mildew? Thanks

You guys are talking about bicarbonate for spot treating bud
rot not powdery mildew correct?

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I’ve got a question pending on another post I’m hoping to get answered. I’ve seen just a couple spots on my plant that looks like powdery mildew. Was gonna use the milk/water/h2o2 mix for that. Well early this morning while I was shaking the dew off my lily, I mean plant, I spotted white flies coming out of her.
Oh google!
Saw an article about using a h2o2 mix to get rid of the flies. Would that be doable? Two birds with one stone so to speak? Thanks for any replies.
@latewood @MacGyverStoner @Countryboyjvd1971 @Willd

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Thanks! I know what I’m doing this fine fall morning. Hand me that baking soda! Wait… maybe coffee first.

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Yes! -of course. -do a web search on it… knowledge is power. :wink: always
read and read & apply it. Then you’ll,- “know it.” - -then spread your
knowledge. :slight_smile:


Thanks very much checking it out reading up and going to treat tomorrow thanks a bunch