Has anyone defeated powdery mildew?

Oh yeah, don't apply any foliar sprays just before or after the vape.

beacher said:

Bleach sprayed on the plants? It doesn't kill them?

Most of my grow areas have 2 fans up top and one at floor level. Tons of airflow, I've often spotted pm first on leaves that are directly under the light and constantly dancing in the wind...it really doesn't make any sense lol

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No, keeps roots from rotting in dwc. Small amounts of bleach, like 10 drops in a bucket. Ivory soap water works wonders too for mold and bugs. I was vexed to when wind dancing leaves got this. I would not try the bleach unless it was an emergency believe me. Never had the issue with promix, only DWC. If and when I start again (I am interested in growing food vertically now) I would use promix with a drip. I think removing it from the tap water is what started my problem. The mold started in the water and in fake promix I made myself. The promox used to kill and prevent all that stuff, Promix BX is magic.

beacher said:

@MidcoastOrganic yep, I've tried that one too. Most of these sprays (milk, h2o2, potassium bicarb, baking soda etc) I think would work fine for someone with an occasional minor problem, but mine is more ongoing...I need a nuclear option lol

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I hear ya! I had a battle last year outdoors with WPM, towards the end of the season. I also used MKP to some benefit, as well as the aforementioned LAB spray, but it was a damn struggle no matter what I used, it always came back. I made sure to select resistant and quick finishing strains to run outside this year (Dinafem Critical+ 2.0).

Good luck to you in the fungus war!

Edit - Importantly, I only had WPM issues when I switched to my custom living organic soil. I never had the issue when running nutrient salts.

So it seems like both of you suspect a certain medium contributed to the problem. This is something I've never really considered before...

I use a brand of prepared coco called mokoko and I used it for months before having an issue. Maybe I'm into a bad batch or something.

beacher said:

@FlakeyFoont sweeping makes it sound pretty badass lol. And I'm way ahead of ya on training plants to be open, since this has stated I've become merciless about defoliation and training to allow for light/airflow

I've never worked with it but I'm definitely aware of the dangers of UV and would obviously take all precautions if I did try. So these lights are made to sanitize air going into HVAC systems? That's cool it's like those UV water systems..

Did you fry your plants when you started? Was fixing it a matter of less time, or less light?

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The CleanLight comes with some chintzy glasses and gloves, and I wear them religiously!

And, yeah, I fried the plants like chinese noodles. UV-c may also alter DNA, good thing I'm not a breeder, so there's no telling what else the overexposure did.

It was a matter of both, I wanted that shit gone, lol!

Lol well lesson learned there I guess. 2 more questions and I'll stop harassing ya

How often do you have to sweep? And lastly have you seen any pm at all since you've started?

More fans. I am dealing with my own mold/mildew problem and though I'm not yet finished this harvest (5 weeks in) I have come to learn that PM spores can really only set it on dead spaces of air (air that's not moving). So if you have enough oscillating fans to make sure there is no dead air space under the canopy you will stave it off.

Also with my very minimal DIY skills, a 6" flange some cardboard and a HEPA filter (MERV13) I made two of these intake filters (see pic) so that the only air getting into the tent is clean. I have no evidence that this will or won't prevent mildew/mold but I figure if the only air they get has been filtered the chances of there being spores in there is minimal.

Humidity can also be a problem, if you can get a dehumidifier in there during flower it might help to keep RH in check, although that can be a costly option, a decent one is like $200+ (CDN). Speaking of costly you can purchase any portable UV-c light for as low as $100 and it will work as effectively as long as it's producing UV-C between 100nm to 280nm. You have to consider too that for any UV-c lamp to be effective it must be very close (~2") to the target, so you can't just sweep it over your plants you need to go into every nook and cranny. HVAC UV-c lights have also been around forever to prevent mold in basements/etc. so you might want to consider one of these to sterilize the air coming into your tent if you're willing to drop $500 lol.

Good luck, keep us posted on your progress in staving it off. Fuck mold and fuck mildew.

Awesome stuff, thank you. Although I will say after going through this for months I now doubt alot of the information about PM online.

For example I've seen it first appear on fan leaves directly under the 600 hps that away in the breeze of multiple fans 24/7. In fact it often seems to appear on those moreso than shaded low leaves that have far less airflow around them.

Another one is humidity. I have much less problems with PM down there in the summer when the humidity tends to be 60+ vs other times. My humidity has been 50 or less all winter down there and it's been the worst it's ever been.

I have a dehumidifier, 3 fans per room under and over canopy, a cold return refreshing the air in my basement all day etc etc and it just keeps coming back.

I wasn't aware ofthose UV lights until flakeyfoont showed me in this thread, but I'm thinking that might be my best option. I'll have to obsessively sweep the whole basement daily for a while, but at least there's a chance I can eventually kill all or most of it for good.

Sweet filter by the way, I should make something similar myself. Even without pm it's a nice touch!

I had pm my last 2 grows. This did it for me...here's what my plants look like now. It's also safe, organic, and won't burn your house down, lol...

For me definitely new medium, spoiled by anti-fungal function of the promix. Not trying to be an overlord or anything. Just my honest experience. Tap water would probably be better than Zero Water was because it is resistant to fungi and mold. Had to end up putting chlorine right back in.

@manfredo cool, that product is new to me...looks very promising thanks. Did you use the regalia and the stargus? How much do you dilute it? It ain't cheap haha

@ChristianGrowsitCrews it happens. I had this issue the first run I did here with promix too, now I'm in coco. All Tapp water too btw, mostly just because I'm cheap lol

beacher said:

@manfredo cool, that product is new to me...looks very promising thanks. Did you use the regalia and the stargus? How much do you dilute it? It ain't cheap haha

@ChristianGrowsitCrews it happens. I had this issue the first run I did here with promix too, now I'm in coco. All Tapp water too btw, mostly just because I'm cheap lol

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I'm using Regalia and Venerate by Marrone, and then Armor Si by GH.

Really the Regalia is the one for pm, and you use 30 ml to a gallon of water... so a quart will last a long time. I think I figured out it costs me under $2 a week to use it, with like 20 plants.

Oh cool, it's not one of those '500ml per gallon' things where a bottle lasts 3 days lol. I'll have to see if I can find it Canada, thanks

I bought a new tent / filter / cleaned all my equipment and got pm again. First grow in a actual tent. My humidity never went over 50 in flower and it just attacks my buds. Never in veg always in flower. I have a 6 inch fan and filter in a 4x4 so airflow is not my problem. I saved 3 outta 4 plants keeping on top of it but I’m so sick of dealing with it. My humidity is like 40 most of the time. I have 3 isolating 6” fans Also going. I just can’t catch a break.

I'm harvesting now with zero signs of pm, after my last 2 grows did have it even after cleaning and replacing everything. Regalia was my savior. I won't even think of not using it now!! Did i mention it's certified organic?? And my RH is not as low as I'd like, usually 45%-55% in flower this time of year.

manfredo said:

my RH is not as low as I'd like, usually 45%-55% in flower this time of year.

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Yes same here. Only hits 50 after feeding which I need to Start doing early in lights on

I thought I had it beat with my Ethos Sour OG Cheese and slacked for 7 days. This plant had trichomes that I thought was pm. When I realized it was just loads of trichomes I laid back. Well checking for ambers yesterday I got a wake up call. It came back and back with a vengeance. It may have been invisible on the surface but inside the buds which were rock hard was loaded with pm. When I did the H202 bath they lit up bright white from the process. I should have took photos but was to pissed off. This plant was stacked with trichomes.

As others have said, pm is soul crushing!! Yeah, get some Regalia and you'll be soon done with it!

manfredo said:

As others have said, pm is soul crushing!! Yeah, get some Regalia and you'll be soon done with it!

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My wife just Doesn’t understand. She’s like , looks like crystals to me. Non smoker !!! Lmfao.