About powdery mildew

how many weeks into bloom can you spray Hydrogen peroxide mixed with water to wash away powdery mildew

im not sure if this helps, but one of the last plants i chopped, i dunked into h2o2 water, 8oz mixed into 5 gallons, submerged about 5 minutes. then rinsed thoroughly with fresh water, and then immediately hang dry with a fan blowing directly on them. theres a youtube video with jorge cervantes that i thought was pretty educational.
Ive never actually tried h202 mixed with water to spray, but i have used a fungicide i got from the grow shop, and used it all through harvest and was ok, except now the buds smell like feet.

Buy online a bulk amount of Horsetail grass tea from a health food supply.

Brew it as directed and make enough to fill your 36oz spray bottle.
Fill the bottle with the cooled tea and spray your plant as needed to kill PM right up until the day of harvest with this stuff....Works GREAT and long term too. Organic and the plants like it like a foliar feeding!

Best damn PM control I have ever tried!

Neem oil is safe…I've used it up to within three weeks of harvest…luckily never had a reason to use it past then. For PM anyway. It's OMRI certified. I added Neem Seed Meal to my soil, it's supposed to systemically guard against molds and mildews.

I hate Neem. This stuff is so overused it has lead to insects immune to it ...The key word is oil.....no oil's on plants and I don't give a rats ass if it's organic...

The whole "board" that votes on what is to be labeled organic is so corrupt......It has chemical/insecticide company officials on this board.....every year it votes on compounds made by these companies to be on the omari list......Some are in and some are not....It simply boggles the mind what some things actually get on the list......and some that don't!

There is my 2 cents on Neem, Rosemary, Cinnamon and Tyme oil's!

PM sucks ass, especially during flowering. Nothing will get that nasty shit out, diluted milk, h2o2, all a bunch of horse shit. You can try washing off the buds, but the PM willl be all over the nugs, even inside. If you smoke that shit with pm, you will end up with a sore throat, but it wont kill ya.
i'd blast it all into oil/hash.

Khronickush,
I just dealt with this problem and did not have any issues with plants that were 1 week from chopping.

First thing I did was wash what I could off and carefully removed leaves that had any sign. I used bleach/water in a fairly strong mixture to clean all the floors, walls, venting...

Then, I mixed 1Tbs hydrogen peroxide/1 gallon water and sprayed everything again, but this time I soaked the plants, soil, buckets... one day. I left the lights on, but turned off the ventilation until all was dry. The next day rinsed plants with water. Did this twice(4 days total) and everything is popping again!

Next, I am rinsing the plants and soil only with 8Tsp Organic Apple Cider Vinegar/1 gallon water on a bi-weekly basis.
Good luck

I will use the peroxide wash on the room, but not plants, on a monthly basis, unless I need it more frequently.