Powdery mildew and high humidity

Bluebuddha · Dec 18, 2022

Well I've got a big problem. I didn't realize that 145 gallons of rdwc and a small space would really get jacked with high humidity.

I got really bad once they grew and really started transpiring.

I actually had to get humidifiers when they were small. Now I've got 2 tents full and the humidity is off the charts. So much so that my inside windows are dripping.

I ordered a small dehumidifier for the F tent but it's barely keeping it at 65%.

I need to get a large dehumidifier and not sure what I should buy. I once saw a formula on how large for every gallon in the room. Anyone have that?

Any recommendations on larger dehumidifiers?

Bonus though is at least the cold isn't drying my skin out..lol ugh

Observationist · Dec 18, 2022

Bluebuddha said:
Well I've got a big problem. I didn't realize that 145 gallons of rdwc and a small space would really get jacked with high humidity.

I got really bad once they grew and really started transpiring.

I actually had to get humidifiers when they were small. Now I've got 2 tents full and the humidity is off the charts. So much so that my inside windows are dripping.

I ordered a small dehumidifier for the F tent but it's barely keeping it at 65%.

I need to get a large dehumidifier and not sure what I should buy. I once saw a formula on how large for every gallon in the room. Anyone have that?

Any recommendations on larger dehumidifiers?

Bonus though is at least the cold isn't drying my skin out..lol ugh

Turn the AC on lol.

Defoliate?

SweetLeafGrow · Dec 18, 2022

Dehumidifiers work to condition the room where your tents are located but hydro introduces that new dynamic of high RH levels. I too found this out the hard way, luckily it wasn't during flower or any critical time and there was no damage done. I use an inline fan to pull moist air out of the tent and dryer air in through intake vents. If you get a fan with adjustable speed, you can dial it in pretty good with just that fan and a dehuey in the room if needed.

freezeland2 · Dec 18, 2022

Bluebuddha said:
Well I've got a big problem. I didn't realize that 145 gallons of rdwc and a small space would really get jacked with high humidity.

I got really bad once they grew and really started transpiring.

I actually had to get humidifiers when they were small. Now I've got 2 tents full and the humidity is off the charts. So much so that my inside windows are dripping.

I ordered a small dehumidifier for the F tent but it's barely keeping it at 65%.

I need to get a large dehumidifier and not sure what I should buy. I once saw a formula on how large for every gallon in the room. Anyone have that?

Any recommendations on larger dehumidifiers?

Bonus though is at least the cold isn't drying my skin out..lol ugh

Buy the biggest dehumidifier you can afford. Auto drain and wifi capable are nice features to consider too.

Goodshit97 · Dec 18, 2022

Bluebuddha said:
Well I've got a big problem. I didn't realize that 145 gallons of rdwc and a small space would really get jacked with high humidity.

I got really bad once they grew and really started transpiring.

I actually had to get humidifiers when they were small. Now I've got 2 tents full and the humidity is off the charts. So much so that my inside windows are dripping.

I ordered a small dehumidifier for the F tent but it's barely keeping it at 65%.

I need to get a large dehumidifier and not sure what I should buy. I once saw a formula on how large for every gallon in the room. Anyone have that?

Any recommendations on larger dehumidifiers?

Bonus though is at least the cold isn't drying my skin out..lol ugh

So im confused by the title, do you have powdery mildew right now?

Bluebuddha · Dec 18, 2022

Yes. Powdery mildew on the lower leaves. I've been fighting it with southern ag foliar applications. At least that's what it looks like.

MIGrampaUSA · Dec 18, 2022

Are you in flower yet? Southern Ag's Garden Friendly Fungicide isn't recommended on flowering cannabis plants. Dr Zymes is supposed to be safe up until the day you harvest.

The problem with WPM is once you see the white powdery stuff on the leaves, the fungus has already taken hold and its very difficult to get rid of. You can battle it with some success, but expect to be battling it until the end of the grow. Also once it's inside your grow area, without proper cleaning/sanitation before starting a new run, you can easily be infected again. I just went through this and decided this morning to cull the infected plants. I still have the cleanup process to do.

If you decide to ride it out, be prepared for a lot of work. I decided it was easier to cut my losses now and get ready to start a new run.

Ponky · Dec 18, 2022

Get you a UV flashlight. And every day right before lights on look with the UV light to see if the spots are spreading.

Bluebuddha · Dec 18, 2022

Not in flower. Damn, I really don't want to cull everything. This sucks. I probably have to though. Sad

MIGrampaUSA · Dec 18, 2022

Bluebuddha said:
Not in flower. Damn, I really don't want to cull everything. This sucks. I probably have to though. Sad

You might have a fighting chance then. First, although it does take humidity to activate the spores, powdery mildew will still thrive in dry conditions so drying out your air is only a start. You'll also want to manage higher night time temperatures. Shoot for above 72F. 75F would be better. Powdery mildew will run wild if left unchecked and temperatures during darkness are in the 60F to 72F range. Add air flow. Those leaves should be dancing in a fairly strong breeze 24/7. An oscillating fan or several of them will provide that airflow. It's airflow that prevents activated spores from grabbing onto a leaf and spreading. Continue with the Southern Ag product since you're not in flower yet.

Edit: Mix the Garden Friendly Fungicide fresh for every application and use distilled water when you mix it.

Anthem · Dec 19, 2022

Bluebuddha said:
Not in flower. Damn, I really don't want to cull everything. This sucks. I probably have to though. Sad

If you are not in flower, I have had great success with fine ground sulphur. I think 5 pounds and a duster are under 20 dollars. Just go into your grow tent with a respirator and a small fan. Dust in front of the fan and point at the plants. The idea is to coat the whole plant in sulphur. PM and Sulphur do not like each other. This practice is widely used in the grape industry.

Bluebuddha · Dec 19, 2022

This is what I'm seeing. Powdery Mildew?
It doesn't fluoresce under a uv light though.

ninjadip · Dec 19, 2022

Can you defoliate? Less leaves, less perspiration, less humidity.

Do you have good air flow in the tent?

Here is a sizing chart I found. But I would just get the biggest one you can afford. You could set it up to drain back into your res, and never have to worry about draining it.

Moe.Red · Dec 19, 2022

Bluebuddha said:
This is what I'm seeing. Powdery Mildew?
It doesn't fluoresce under a uv light though.

Does it wipe off?

Observationist · Dec 19, 2022

Milk peroxide defol

Ponky · Dec 19, 2022

You have an ultra sonic humidifier in there by any chance?

RootsRuler · Dec 19, 2022

Bluebuddha said:
I once saw a formula on how large for every gallon in the room. Anyone have that?

[Number of plants] x [Gallons per day per plant] x 8 [Gallon to Pint factor] = Recommended Dehumidifier performance.

I like to buy the dehu's with a drain hose feature and dump the water into my reservoir. Ran a tent for 6 weeks on just dehu dump.

Shaded_One · Dec 19, 2022

@Moe.Red and @Ponky are on it. Find out if it's actual PM or just mineral residue from your humidifiers first

Bluebuddha · Dec 19, 2022

It doesn't wipe off. It just sticks. Like crystalized sap. But, after looking at pictures of PM on the Internet, it does look very similar.

I have a 6 in acinfinity fan and filter running continuously at 5 now, before it was 2. 1 acinfinity oscillating fan and another 6 inch fan pointing at the tops. They never turn off.

This tent doesn't have a humidifier and they went straight from clone tray to F tent.

I'll continue to treat as if it were PM and see how it goes.

Ponky · Dec 19, 2022

I would defoliate 100% off the lower halves. And possibly Sulphur the top of the soil.

Powdery mildew and high humidity

Powdery mildew and high humidity

Bluebuddha

Observationist

SweetLeafGrow

freezeland2

Goodshit97

Bluebuddha

MIGrampaUSA

Ponky

Bluebuddha

MIGrampaUSA

Anthem

Bluebuddha

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