Oh no white mildew

What a shorter I have over crowded my grow and messed up my plants. One is just showing signs of it it is bout a week or two grime from harvest. I also have one that is full and is still bout three weeks away and one that is starting and is about a month from harvest. Please help me save my plants. I also have several little guys in there that have just started from clone or seed. @garrigan62 @raustin @WickedAle

first u need to separate sick plants. improve circulation, think exhausting air, reducing humidity, fans on plants. and medicate ur plants, i think you can use a diluted hydrogen peroxide spray. lets see what others say

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K gonna move up around right now will be back. I’m freaking out so much work hope I didn’t bugger up

Yup, I do 1 cup HP to 1 gal water and spray plant down.
Worked wonders when I got WPM on my outdoor girls.

So is ok to do to one that is that far along into flower then. I read in my book that baking Sofia and water will stop it from growing

Also will am venting system help with that. I have clean area but I got over crowded. I though u would be ok though because humidity is pretty low

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Here ya go my friend.

What causes White Powdery Mildew?

High Humidity

WPM needs moisture to thrive, but that doesn’t necessarily mean it needs water.
Having a grow area with
high humidity is all WPM needs to grow. This seems to be a bit problematic since
young cannabis plants
grow best in relatively humid environments (40% -60% RH). Luckily, high humidity
usually only becomes an
issue when it’s combined with the next cause (low/no airflow).

People who live in environments with extremely high humidity (such as Florida
and the UK) can purchase a
dehumidifier to control humidity in the grow area. This is especially important
during the flowering phase
when humidity needs to be much lower (45% rh) to prevent rampant growth of WPM
and bud mold.

Low/No Airflow

White Powdery Mildew has a hard time settling in a grow room where the air is
being moved. High humidity
will give WPM the conditions it needs to survive, but poor airflow is what gives
it the ability to settle
down in the first place. In fact, a small (preferably oscillating) fan moving air
in a grow area will prevent
the vast majority of White Powdery Mildew woes.

Poor Ventilation

If you have WPM spores in your grow area and the air in grow area is never
exchanged for fresh air, the
spores get multiple chances to land on your plants and reproduce. This happens
most often in conditions
where cannabis is being grown in a closed, unventilated space - such as a closet -
and precautions aren’t
taken to exchange old stale air for new fresh air.

Leaf-Leaf Contact

Leaf to leaf contact = moisture = White Powdery Mildew!Leaves that are touching
each other will form
moisture between them, and thus they become more likely to contract WPM. Untrained
bushy/leafy plants
with lots of new vegetative growth are especially prone since plants will often have
leaves mashed up
against each other as they try to reach the light.


Yes I have just read your older post I’m going to try some of your method to get rid of it. I have just gotten ahead of myself and have way to many plant in the go. But I’m building new 5x10 area to expand. I have also just gotten a bentfan and carbon filter. For the one room. Wo this is a lot of work for sure.


You’ll be just fine. We are all here ready and willing to help you through this.
A lot of people here are going through the very same thing you are and they are all turning out ok
Any time you want or need some help, just tag me and i’ll see what I can do to help ya


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Thank you kindly. I’m wondering I’m going to use some apple cider vinegar to start as a spray. Now should I spray the ones that are flowering or not. Also will me setting up a filter and fan pushing out air help with this situation. I have some young girls just starting and so don’t want to lose the one strain @garrigan62

Oh and also when should I spray I’m afraid of getting even more lift burn lol

Then do it just before lights out

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