I'm growing out this Blueberry/Raspberry Hybrid - Clone only from up north. Man oh man every time it finishes with the craziest blueberry smell - Big UPPP MrBuBBa
Go get some serenade spray right away or at least wash them off with a spray bottle and gently try to rub that stuff off....you can bring them back no problem, but i think ventilation is key when dealing with powdery mildew...get a fan on them. They will survive for sure!!!
Also some people just have to use a sulfur burner every once in a while in addition to a dehumidifier. I personally had a small attack of the PM on another strain I am preparing that I dealt with today. Not quite as bad, but you could see the spots for sure on mine. I cleaned them up and they're gonna be cool....You plants look healthy otherwise, just as mine were.
Shit dude, you have some serious mold issue .I hope and think that they are going to recover. Put a fan like said above.
Can't wait to see LA and bluberry flowering