I have rampant powdery mildew. I have 2 dehumid + air conditioner, temp is well regulated. Can't figure it out. Any other suggestions? My big question is I also had it in veg and sprayed twice with neem, it worked quite well for about two weeks each time, now those plants are in flower and I have alot of leaves yellowing and dying- ph is good, ppm is good, I saw somebody say that neem can clog the underside of the leaf, could this be the yellowing? All suggestions and comments would be welcome! Thanks.

neem can cause clogging of the pores of the plant,if u spray with neem or any substance really u should take 2 sponges and wipe down the leaves when u start to notice problems,your plants can suffocate.i would also buy a cheap humidty gauge to see if your current gauge is potentially giving u the wrong readings.do u have any mold anywere near your grow space? have u tried a sulfer burner?

No mold, the space is quite clean, I have never used a sulphur burner. How effective is it? How many times can I do it with out harming the plants? I am going to try it I think. Or I may spend 20hrs wiping leaves...LOL

Hi chickweed welcome to the forum!!

I saw this and thought it may help you.
Its Organic
Safe Gro Natural Mildew Fungicide 1 quart

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The thing with powdery mildew is that its a fungus, so if you don't get 100% of it, it can spread very easily. Wish I could be of more help, but my advice would be to brush it onto your leaves and hit every spot you find it on. Good luck!

WOE!! This is my VERY FIRST reply!!!!!!!!

I have the white powdery mildew as well I went down and bought Eagle 20, spray that sh** on my girls just once, and i have NEVER seen the WPM since!!!!!!!!

it doesnt mean that I will never come back though. If it does, then I will buy a sulfer can