How To Organically Clean A Room After Powdery Mildew Outbreak?

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One drop

One drop

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As well as getting you area clean ready to go again if you have pm probs on your plants which I sometimes get on my outdoor crop I spray with 1 lt of full cream milk mixed in 9 lts water spray both underside and surface of leaf this will give the PM some nice food other than your plant my Tutor at Hort school said the PM feeds on the bacteria left by the milk and starts to over fees and dies out again I use it and even in my tomatoes that have suffered from it and it's organic I would use anything else .
 
DrMcSkunkins

DrMcSkunkins

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Hydrogen peroxide vinegar infographic thumnail 300 x 388
Two pump sprayers one distilled vinegar, the other peroxide and water and some shammy towels.
http://cleaningbusinesstoday.com/blog/hydrogen-peroxide-vinegar-a-disinfecting-duo
Dont get the mixture on your skin, hair or clothes unless you want them bleached. DO NOT BREATHE THE MISTS MIXED TOGETHER. Carefully spraying in small batches should help prevent breathing the mix.
 
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Homesteader

Homesteader

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As well as getting you area clean ready to go again if you have pm probs on your plants which I sometimes get on my outdoor crop I spray with 1 lt of full cream milk mixed in 9 lts water spray both underside and surface of leaf this will give the PM some nice food other than your plant my Tutor at Hort school said the PM feeds on the bacteria left by the milk and starts to over fees and dies out again I use it and even in my tomatoes that have suffered from it and it's organic I would use anything else .

I'm not positive on the application (I think I used 3:1 milk:water but that may be too weak) and I have only ever used milk on my squash but in order for it to work, you need bright sunlight immediately after spraying that radiates UV. The UV light breaks down the protein in the milk and burns the PM (which is why it doesn't matter what % milk fat you use as skim or whey protein should be fine).
Here is a good link
https://www.growveg.com/guides/using-milk-to-prevent-powdery-mildew/
 
We Solidarity

We Solidarity

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take everything out of the room and steam clean the carpet, wipe down walls with peroxide (I mix at 5% dilution but have gone overboard with no harm done except to my skin) and wipe down the ceiling. You won't be able to get enough UV in there but if you invest in a bipolar ionization unit you'll be relying on the same principles as UV light and I've found them to be fairly effective for maintaining a higher air quality indoors. Replace your grow tent and any other equipment - that is ultimately most growers downfall. Thinking you're going to clean PM in an effective manner is silly but replacing it works very very well.
 
Perception

Perception

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On that note, do you all think that it makes more sense to use an inclosed grow tent in the room (ie: gorilla tent)? I've just built a pvc frame that holds mylar around a 3'x3' area, and it's not sealed intentionally (big gaps around sides of mylar for air exchange & fans).

I've set everything up with a heavy light-blocking drape over the door of room, and ventilation ducting running under the drape. I blow about 450cfm in to the room 24/7.

So my question is, would I gain any advantage from buying a 3'x3' or 4'x4' sealed tent? I felt like having the open air in the room would benefit the plants more, but am open to other setups.

Picture of my current setup:
IMG 8130
 
DrMcSkunkins

DrMcSkunkins

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On that note, do you all think that it makes more sense to use an inclosed grow tent in the room (ie: gorilla tent)? I've just built a pvc frame that holds mylar around a 3'x3' area, and it's not sealed intentionally (big gaps around sides of mylar for air exchange & fans).

I've set everything up with a heavy light-blocking drape over the door of room, and ventilation ducting running under the drape. I blow about 450cfm in to the room 24/7.

So my question is, would I gain any advantage from buying a 3'x3' or 4'x4' sealed tent? I felt like having the open air in the room would benefit the plants more, but am open to other setups.

Picture of my current setup: View attachment 648357
Tent pros: blocks light so you can do veg and flower in one room cutting your harvest time in half, makes negative pressure and keeps the smell from escaping, waterproof liner at the bottom, more reflective than mylar blankets, sturdy place to hang lights filters etc
Cons: takes about an hour to take down if you have to move things in a hurry
 
DrMcSkunkins

DrMcSkunkins

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There is no more or no less co2 in the open air as there is in your house, you can put the fan venting right into the room if its air conditioned, no need for bringing in outside air.
 
Perception

Perception

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Yeah, tent might be easier in future. The intake fan to the room is to help keep RH & temperature down during light cycle mostly. Gets stuffy otherwise.
 
cemchris

cemchris

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Bleach will kill mold spores you just have to use it at like 30% dilution to be 100% effective. We had someone test it for us since we clean our flood trays with it. Also remember bleach degrades over time even when it isn't opened. Some other things are H202 and Borax. Both good options for carpet. I would steam clean it though with a commercial anti fungicide. Then there is stuff like Physan 20 or Tea Tree oil. This is usually what you use to clean out A/C units after an outbreak etc.

Do yourself a favor. Either take the carpet up (if you can) or cover it and seal it with something like Panda or a pond liner. Not only are mold spores a problem with carpet but battling bugs can be a real bitch with that in there.

The cost of the Mylar is greater then benefit you will see from it.
 
S

slap14

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I used to fight PM quite often. I'm in tents and found an alternating spray of Mildew Cure and Serenade worked very well eliminating it. I clean my tents with Physan 20 and that seems to have controlled the issue, but I'm always trying to be very proactive when it comes to PM.

Good luck it is a pain in the ass

Slap
 
SeedyGirl

SeedyGirl

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Cleanliness is next to godliness.
I have one veg that feeds two flowering rooms. I use physan20 to clean all DWC systems in between cycles and the spray the interior of each room at that time. Pick up all dead matter.
I haven't seen pm in yrs. from other people's clones is a good way to get it.
note I also grow from seeds and clone my own moms. But every once in a blue I take a strain in clone form if I can't resist. but I grow it in a far away land in what I call my rehab. Hit it with floramite. Watch it. For six months make sure it's clean. Then and take clones off it. Once the clones root well I hit again with floramite. Then the best becomes my new mother and travels into the mother room. And the other strong clones will go to veg. Like right now I am in Cali prop420 n looking for a real kk strawberry cough clone. Any help would be great.
 
Eagle.ize

Eagle.ize

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Just finished a grow where I battled Powdery Mildew. Looking for advice on cleaning the (now empty) room before next grow.

The basement room is carpeted, and I have an 8'x8' piece of linoleum on the floor around my 3'x3' grow tent. Tent is not sealed - just has hanging reflective material. I don't have illusions of totally eradicating all PM spores - just want to get it as good as I can, and I'd like to keep the cleaning procedure as organic as possible.

I was thinking about the following, but would love some opinions from others:

-> Spray down everything besides carpet with Vinegar/H20 mixture (maybe isopropyl?)
-> Vacuum well
-> Mist carpet with dilute anti-fungal herbal blend
-> Spray same mist in to intake fan ducting for room with fans running
-> Clean all fans in the room

Thoughts?

What about putting a uv bulb in the room for a few hours in various places?

You are on the right track!.

Ozone. I have used copious amounts of ozone to sterilize new grow spaces as well as reset rooms infested by mites, white flys, gnats, etc. Nothing survives. At high concentrations ozone becomes toxic to all organisms.

Big Blue Ozone generators we use for odor remediation perform double duty in case of pathogenic outbreaks. First, the room must be cleaned out and all living things (including pets) must be kept clear. Next, seal the gaps in the doorways with a towel to tape it off with plastic. Fire up the ozone generator and put a small fan on it to circulate the air. Let it run for 48 hrs. Treat it as if you were bombing the place with toxic pesticides. When it is time to clear it out, open all the windows and doors
to let it dissipate. Do not breathe the air. Ozone will not leave any toxic residue in case you are wondering. This beats getting on your hands and knees.

I hope this helps.
Cheers!
 
Perception

Perception

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Awesome! I'll definitely keep the ozone generators in my back pocket. Was looking at them online recently... kind of middle-of-the-road on cost. Probably well worth it.

Update
I ended up just cleaning the room with a 1:1 vinegar/H20 mix. Cleaned & sprayed EVERYTHING, except the carpet. Couldn't even walk in the room without a respirator or I'd gag. Sprayed heavily. New plants have been in flower for 4 days now, and no signs of PM. Veg closet is clean too and sans PM too (same room).

I bought some GreenCure fungicide (organic) in case it comes back. I've been monitoring the room in the dark with a green light to look for PM and haven't seen any. I'll let you all know if it's a success or not!

P.S. I'm running living organic soil, so there are always going to be some microbes & bugs around. I'm just hoping that I can keep the plants healthy enough that they defend themselves. Plus, the best cleaning I can manage without going nuclear.
 
Natural

Natural

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Heat kills PM too. I'd cover the carpet completely..I got away with tarps stapled in place for years. Using pond liner now.
Keep your humidity in check..especially at lights out..air moving. Like I would add a condensate pump or hose to drain on the dehumidifier..if it shuts off over night the humidity will spike. PM is a bitch when it sneaks in on a clone and your not ready. But really when the environment is right..it's pretty much a wimpy virus and easy to beat ime.
In the future if you want something that doesn't stink..get a gallon of Oxine..it's cheap and you just need to dilute a little in water. It's used in commercial kitchens and flood mold remediation. Kills all mold and virus on contact and breaks down to simple salt. kind of odorless..but mixed strong can sneak up on you and irritate your lungs like a bleach solution.
 
Perception

Perception

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Luckily, I live in a fairly dry climate, and the humidity in room never seems to go much above 50%. I run fans 24/7, and one is always pumping fresh air in to the room.

The winter is actually helping me out in regards to keeping temperatures steady (how the house furnace runs, etc). I also realized that I could run my veg closet on a semi-alternate lighting schedule. So when flower lights go off, veg lights are just coming on (light sealed closet). I pump warm air out of veg closet in to flower room. This helps keep the temperature from dropping dramatically in the room during the flower dark cycle. So basically, there is always a least one light running, and generating heat in room.

Right now, I'm seeing temperature fluctuations of about 8deg F, which I'm happy with. Before I had alternating light schedules, I was seeing 20deg F fluctuations. I think that a big part of the PM problems were temp fluctuations.

@cannabeans put me on to the temperature fluctuations. I just remedied the temperature issues, so we'll see how things go! Thanks Cannab
 
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Natural

Natural

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Luckily, I live in a fairly dry climate, and the humidity in room never seems to go much above 50%. I run fans 24/7, and one is always pumping fresh air in to the room.

The winter is actually helping me out in regards to keeping temperatures steady (how the house furnace runs, etc). I also realized that I could run my veg closet on a semi-alternate lighting schedule. So when flower lights go off, veg lights are just coming on (light sealed closet). I pump warm air out of veg closet in to flower room. This helps keep the temperature from dropping dramatically in the room during the flower dark cycle. So basically, there is always a least one light running, and generating heat in room.

Right now, I'm seeing temperature fluctuations of about 8deg F, which I'm happy with. Before I had alternating light schedules, I was seeing 20deg F fluctuations. I think that a big part of the PM problems were temp fluctuations.

@cannabeans put me on to the temperature fluctuations. I just remedied the temperature issues, so we'll see how things go! Thanks Cannab
that is a big one..for me it was a winter issue I had to square away..when the temps dropped the humidity in the warm air would just dump condensation on the leaves. good for mushrooms..weed..not so much. Last winter/spring was a tough year for just about everybody it seemed. The stuff floats through the regions like a death cloud sometimes. Just make it inhospitable. I found it sets in as a clear blotch in veg and if not dealt with will go full white mold in flower and the night cools and humidity dumps make it flourish. Keep your air exchange and fans going good in veg..make sure the light is bright. That's where PM gets it's foot hold really. It's a good time to foliar plants with an ewc tea and I like to use a horsetail herb tea..that can be a preventative as well as a cure in flower. Also a high brix level helps.

Blurb from Connell opoened my eyes a bit ..

Powdery mildew develops quickly under favorable conditions because the length of time between infection and symptom appearance is usually only 3 to 7 days and a large number of conidia can be produced in a short time. Favorable conditions include dense plant growth and low light intensity. High relative humidity is favorable for infection and conidial survival; however, infection can take place as low as 50% RH. Dryness is favorable for colonization, sporulation, and dispersal. Rain and free moisture on the plant surface are unfavorable. However, disease development occurs in the presence or absence of dew. Mean temperature of 68-80°F is favorable; infection can occur at 50-90°F. Powdery mildew development is arrested when daytime temperatures are at least 100°F. Plants in the field often do not become affected until after fruit initiation. Susceptibility of leaves is greatest 16 to 23 days after unfolding.
 
CaliRooted

CaliRooted

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Just bleach everything and get a product called Procidic2 and done
 
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