White powder mold control and treatment

I’ve used neem oil, with some success, I’ve read about hydrogen peroxide, and greener cleaner.
What other products have been considered safe if any for use in flowering (and veg) both as a preventative, and control?
I’m just exploring options based on everyone’s feedback, so that everyone can assist everyone that may be having issues. There might be a product I wasn’t aware of, and same goes for other growers. This thread should be helpful condensed information.
Neem oil (self explanatory)
Greener cleaner (if anyone has a link)
H2O2 (self explanatory)

@Hellraiser @imSICKkid @MattyBear @dbrn32 @Myfriendis410 @Mark0427 @yoshi @kaptain3d @Bulldognuts @KeystoneCops @Dman1969
As always tag someone else who needs this, or can add to it! :sunglasses:


A dilute baking soda spray (with distilled or RO) can be useful for treating mold that develops near the top of the soil.

Don’t forget that management of humidity is the safest and most effective method and actually prevents mold/mildew rather than treating it after you already have it.


I’ve never gone past using peroxide. It will dry leaves out and make them papery but the alternative is far worse. Start with a dilute mix in distilled water and increase strength as needed. I see a weak solution (1/4 cup/gallon) used every 24 hours until harvest.


I used this about 2 weeks ago and just chopped. Leaves did dry out quite a bit for real lol. Ill let u know if it alters taste or not. So far smells wonderful. These plants been thru hell and back already tho.


Aside from changing the environment and cleaning, the only thing I’d use would be foliar application of a lactobacillus culture.

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Thanks for the tag, I haven’t had to deal with WPM yet. Key word yet, so having a thread covering this subject will be a positive thing.


For everyone else this is yogurt.

@KeystoneCops is there a particular ratio you follow? Example 1 cup in 1 gallon?


Thanks for the tag :label: Brother. :pray: I haven’t had this problem yet but it will be extremely nice to have this thread :thread: when it does happen and I’m sure it will. :sunglasses::v::call_me_hand:

Not exactly, but you make your own culture from milk. It’s easy to find instructions.

I’ve always used 10:1 water to LABs, but that’s a holdover from using water and milk in the same ratio for outdoor. So I don’t know for certain what ratio is optimal. It’s probably important to use chlorine-free water though.


@shindig153 uses it he may have a link. :sunglasses::v::call_me_hand:

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I spray my wife’s rose bushes with whole milk when they get WPM, it works. As far as my plants, I’ve used neem oil in veg the one time I had WPM and it cleared it up, never had it during flowering but if I did I would probably try the peroxide/water mix or the baking soda, or heat.

I’ve heard of growers using high temps to eradicate WPM in flowering, get tent to over 95F for a 12 hour period, never tried it as I get WPM so rarely (once in 30 years).


Are you referring to the use mildew eating bacteria in your foliar spray? I have tried this with Orca® Liquid Mycorrhizae - with Beneficial Bacteria in rotation with H2O2. Seemed to help in short term, but it always comes back.

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I kinda skipped past it, but like @Hellraiser mentioned, my first step would be to address the environment. You can’t eliminate mold spores (in a humble home grow), but you can keep them from flourishing. An hour at 95f each day will stop a lot of pest issues. Keeping your relative humidity below 50% in flower helps too. Moving air to eliminate microclimates helps.

I’ve never had a cannabis plant that was really prone to PM, but if I did I’d try all those steps before spraying.


I had not considered using heat as a method of eradication, but that makes perfect sense. I would guess that earlier in to flower would be better then later as terpenes might be impacted and evaporate.

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Not to be the bear of bad news, but you just don’t want to get it, prevention is the key. I’ve been battling it for quite some time. I’ve wasted lots of money on many different treatments. I have had my room 140° for 2 days and and still have it. Of course with no plants in it. My only cure has been chopping, an burning. Preventing it is most important, I had a strain that had it systemically didn’t know it, ruined many plants

Regalia an Green cure work good for prevention in rotation. Should be Veg an early flower only.

Do you think the UVA lights help with WPM?

I will be disassembling this current setup by the solstice, and sterilizing the area. Hope to have minimal downtime.

If it’s on the Bud’s it can be dangerous to smoke. Some people wash with peroxide and water but I strongly recommend not to, kills spore’s but still there, and not good for your lungs.

Trifecta… crop control…