White powder on plants ?

It looks like the beginning of powdery mildew. It will get much worse quickly, and spreading to other plants. Get on top of it, wash the leaves thoroughly. I have used baking soda but didn’t work well, so I would use a good fungicide. Reapply regularly, powdery mildew can wipe plants out. Keep humidity lower and try to raise the temperature to 80 degrees fahrenheit.
 

Renfro

Well-Known Member
If you have a large grow, like a room and not a tent, look into a sulfur vaporizer. That and a product called AirROS by Sage Industries are the only things I have found that will actually get rid of PM forever. Treating the plants with bullshit like baking soda or H2O2 will slow PM down but I fear you will find that when you hit later flowering the PM will come on with a vengeance and by then you can't use a lot of methods.

There are some biological fungicides that you can try like Actinovate, again they will slow it but not eliminate it in most cases.

The big problem with PM is foliar applications, no matter how strong, are rarely able to achieve 100% coverage. PM is tough and has managed to build resistance to many products. Even Eagle 20 (skip using that) used to be way more effective than it is now due to resistance. One thing that really stops PM is raising the pH on the surfaces of the plant. This is what baking soda tries to do and what a sulfur vaporizer actually does (it gets 100% coverage).

A lot of people will say the sulfur vape is bad, it is not something you wanna breathe. If your grow room is sealed up pretty well then you can use a sulfur vape IMO. I won't put a plant into a new grow room until it has been vaped, well that used to be my routine before I got an AirROS unit. That device will sterilize all surfaces the air touches and it will do it 24/7 without harming your plants and while also controlling odor.

Best of luck in your battle.
 

MICHI-CAN

Well-Known Member
If you have a large grow, like a room and not a tent, look into a sulfur vaporizer. That and a product called AirROS by Sage Industries are the only things I have found that will actually get rid of PM forever. Treating the plants with bullshit like baking soda or H2O2 will slow PM down but I fear you will find that when you hit later flowering the PM will come on with a vengeance and by then you can't use a lot of methods.

There are some biological fungicides that you can try like Actinovate, again they will slow it but not eliminate it in most cases.

The big problem with PM is foliar applications, no matter how strong, are rarely able to achieve 100% coverage. PM is tough and has managed to build resistance to many products. Even Eagle 20 (skip using that) used to be way more effective than it is now due to resistance. One thing that really stops PM is raising the pH on the surfaces of the plant. This is what baking soda tries to do and what a sulfur vaporizer actually does (it gets 100% coverage).

A lot of people will say the sulfur vape is bad, it is not something you wanna breathe. If your grow room is sealed up pretty well then you can use a sulfur vape IMO. I won't put a plant into a new grow room until it has been vaped, well that used to be my routine before I got an AirROS unit. That device will sterilize all surfaces the air touches and it will do it 24/7 without harming your plants and while also controlling odor.

Best of luck in your battle.
Enlighten me. I have a minor PM problem in a 20'x10' tent. Week 4 of flower. What is your suggestion. Peroxide at 6% is slowly winning. But labor intensive. All my old school self knows.
 

Renfro

Well-Known Member
Enlighten me. I have a minor PM problem in a 20'x10' tent. Week 4 of flower. What is your suggestion. Peroxide at 6% is slowly winning. But labor intensive. All my old school self knows.

Their smallest unit is a fit for your space. It's a 2000 cuft model but we use a multiplier of 1.5 for flowering so it's a good fit IMO. Call Sage and ask for Michael Alaman, he will get you setup.
 

MICHI-CAN

Well-Known Member

Their smallest unit is a fit for your space. It's a 2000 cuft model but we use a multiplier of 1.5 for flowering so it's a good fit IMO. Call Sage and ask for Michael Alaman, he will get you setup.
Yah. No thanks. Type c UV inline is cheaper and no replacement or maintenance costs for years. As a home hobbyist I applaud your effort. Peace.
 

MICHI-CAN

Well-Known Member
That won't sterilize surface though but hey I tried. lol It's not for everyone but for those that have it the worries of PM, botrytis and the like are a thing of the past.

You may wanna look into a sulfur vaporizer.
Appreciate it. Seriously. Just not for me. Cost prohibitive shall we say. But in line with my green principles. My preferred method is Citrox. Cost $80 a quart to import thanks to Monsuko and Dupnot.
 
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