Powdery mildew in flower!

so i thought i had it completely gone was spraying with neem oil and once i went into flower after a few weeks i noticed it was starting again very lightly and i just kept picking the leaves that had some in it and now im on week 4 of flower and i still kind of have it under control i pick just a hand full of leaves everyday and clear it all out but theres always a few more leaves that have more the next day. im just wondering if im doing this right and just trying to control it or is there a srpay i can use in flower that wont affect my buds i wanted to give it another spray of neem oil but i was wondering if week 3 or 4 of flower is to late to use neem oil because i heard alot of poeple saying spraying neem oil in flower will ruin your buds but never tired it myself. anyone have any advice or am i doing what i should be doing just trying to not spray and pick to keep it under control?

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@kaptain3d has had issues with WPM in the past. He may be able to help with how to control.

I wasn’t able to eradicate it. But I was able to keep it at bay by spraying EM1… Safe to use in flower… And don’t use the neem oil in flower… That’s all I can contribute. :nerd_face:

I think @Hellraiser may have a solution for this :thinking:


Some strains developed powdery mildew and all you can do is keep it at bay. Some plants are too resilient for powdery mildew. I’ve had multiple plants in the tent but only one would get powdery mildew a wedding cake. I treated it with this

same to use during flower?

1/1 peroxide with water in a spray bottle. And wash your buds in a peroxide bath after harvest.


I would agree with @Borderryan22 , I have had problems with WPM in the past and it deff helped. Would recommend a bud wash after harvest. You’ll be surprised on how much stuff comes off of your plants that no one would want to smoke! Good luck!:+1:t3:

Sierra naturals is what worked for me, but a combination of that and lowering humidity ultimately helped me. I now run 40% RH or less.
I was using peroxide, but ultimately it always came back. Peroxide does kill it, but doesn’t prevent it. Peroxide works, just keep an eye on it after application for when to apply again.
This will cause some frazzled leaves applying peroxide, so be aware of that.

Baking soda solution : Mix 1 tablespoon baking soda and ½ teaspoon liquid soap such as Castile soap (not detergent) in 1 gallon of water. Spray liberally, getting top and bottom leaf surfaces and any affected areas. Works for me.

Yep this is what I would do.

On this topic, I was growing 6 plants, 3 Grape Ape and 3 Cali Sour. All 3 Grape Ape had no issues of WPM, and all 3 Cali Sour had issues with WPM. They were in the same tent, under same conditions. So the strain does matter. I just don’t know how to determine which strains are better/worse for the indoor tent I am using. Obviously Grape Ape was good but I can’t find it. Anyone have suggestions on some strains that may be similar? Cali Sour was too fragile I guess. Thank you!!