Mold in my grow room

Question from a fellow grower!

Hi, I am having some issues with my Mango Kush plants that I am currently growing. The plants themselves look good, and the buds are growing nicely, but my grow room has some mold on the walls from humidity and I am wondering if my plants are contaminated or if they can be saved. I don’t see any mold physically on the plants, but the smell in the grow room isn’t good and while I have a fan in there, the room doesn’t have the best ventilation.

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Yeah that mold can affected you plants

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Welcome to the community ! Exhaust fan and circulating fans. good air flow definitely going to be your best friend to head off mold and white Powder mildew. Remove plants from grow room clean Walls, increase air flow. Good luck moving forward.

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I would remove plants push air and heat around a few days and then paint walls with kilz flat white paint. It kilz mold. Don’t play around with it kill it, as mold is bad news.

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Yes it is. WPM is not something you want to smoke. A mild peroxide spray down of the plant and a strong solution of same on the walls periodically will get you through this grow so long as you increase airflow and or reduce the humidity. In many climates you will need to install a dehumidifier. Cleaning up your grow space and improvements to air flow will really help you in further grows as well.

It would be nice to know what your setup is and the general region you are in.

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I live in Minnesota. The mold appeared on the lower walls after we had a big thunderstorm. It was black mold on the lower walls and we cleaned it up and sprayed a mold control spray on it (on the walls not the plants). We have kept the door of the grow room open since then and do have a fan going and also have a dehumidifier. We used our old sauna as a grow room since the heater is broken and we never use the sauna anyways. My friend who has experience with growing who gave us the seeds as a gift stopped by my house today and thought the plants looked very healthy and thought they’d be ok if we cleaned the mold spots off the walls and sprayed solution on the walls which is what we did. We haven’t sprayed anything on the plants, but just wondering by peroxide do you mean just the hydrogen peroxide that people use to disinfect cuts on your skin? Or is it a special product that I buy? This is my first grow and we followed a friend’s instructions on what do to, but I think next time I will want to figure out a different set up.

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Thanks! I have had a fan in the room, and while a dehumidifier didn’t fit inside the grow room, I have one just outside the room and have opened the door of the grow room for better airflow.

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Yes, Hydrogen peroxide that you purchased at the big Box store cut it 50 /50 with water. Lightly Mist affected area . Your dehumidifier in the area you’re pulling the fresh air from should be a big help.

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So you only do the hydrogen peroxide if you see actual mold on the plants? Or do you do it as a preventive measure? As of now I do not see any mold on the plants. The grow room air smells a lot fresher as well since cleaning things up and opening the door.

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Yes that is correct only spray the plant if you see mold or mildew on the plant. Preventive measure would be good air flow.

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So we got more rain today and possibly overnight as well. When I checked the plants today I saw these tiny white patches on some of the leaves. Here are some photos of one of the leaves I picked off and of the grow room set up. I can’t take the plants out of the sauna without possibly breaking branches as they are quite large, so I don’t know if I can get the sauna clean enough, also the walls are wood which is porous and very difficult to 100% clean. I also noticed more mold on the shower area walls again. I am just wondering if I should scrap this whole grow at this point and get a grow tent with proper ventilation and grow some mold resistant auto flower strains instead? Or is the climate where I live too humid to even bother? Minnesota has a varied climate. When it rains the humidity gets really bad. Summers get really hot days up into the 90s, while winters get down to -20 at times. Sure we have AC and a furnace, but even then it’s hard to keep humidity levels stable.The other issue is during fall through spring I have a hot tub in my basement which causes humidity, which I have dehumidifiers to deal with, but am still worried about. My friend who stopped by yesterday thought that my grow looked like it was going to be a success, and my husband thinks we should keep trying. My issue is I have mold ALLERGIES so I’m terrified of even attempting to harvest and smoke this.

I used H2O to disinfect the grow tent before I put anything in it and wipe down with sanitizer and wash my hands before touching anything with my plants . ,Knowing that anything can transfer into your plants than into you. I act like a doctor.

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So far I have done as other comments have suggested with the Hydrogen Peroxide/Water 50/50 spraying on the plants and on the grow room walls. It’s currently being grown in my old sauna, but I was just thinking for future grows maybe I’m better off getting a grow tent and putting it into a cleaner area. I’m getting so close to harvest. We started growing in July and probably have 2-3 weeks until the buds should be ready according to my friend when he looked at the plants. It’s just been stressful not knowing if I should call it quits now or keep trying with these plants. The other thing I am unsure of is do I spray the Hydrogen Peroxide/Water solution daily now? Or just the one time? I should also note I removed the leaves that had mold spots.

I would keep a close eye on your babies and invest in a VIVOSUN Grow Tent we have a 4x4x6ft and I put it up FUN YES. I put it in our basement which runs 68-70 all year but with the tent Everything is provided for you lights and I have adapted Tupperware trays like under the bed kind to hold the 5 gal fabric pots that way water runoff doesn’t go all over I have a adjustable heater in there to keep temp and a fan for air flow and like I said keep it clean. the Tent setup may cost 500-600 but in the long run it will pay for itself by the 1st harvest. Don’t give up learn from your mistakes and finish this batch and start fresh with a new setup Pax Spudeater56

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Oh so you have the Vivosun 4x4x6 grow tent? How do you like it? I actually was looking at grow tents on Amazon and have that one on my wish list. I’m fine spending some money on a better set up. I’m just curious do you have to buy the exhaust fan to the grow tent separately and if so is there a particular model you recommend? Amazon had a couple that were recommended as frequently bought with that tent but I still am not certain what is best. I know I’m at least capable of getting the plants to grow, it’s just a matter of having a better grow environment. Our house usually stays in the mid 60s to low 70s. It’s just the humidity I worry most about. I have a large basement 1600 sq ft so there’s a few different spots I could put a grow tent. I just worry about my hot tub causing too much humidity though if I use it this fall through spring, so that’s my other issue… Do I just not use my hot tub anymore or just hope the dehumidifiers are enough? Hot tub is currently empty and not in use, we were going to wait to fill it after we were done with harvesting, drying and curing. I do have 2 dehumidifiers I use during the seasons I use the hot tub though and could easily buy a couple more fans to circulate air. I also purchased a hygrometer off Amazon so I can keep track of the temp and humidity as well.

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Hi Jkali, welcome to the forum. Sounds like you have a good plan going forward on mold intervention. Just as an FYI, MrClean? yeah, that simple little cleaner not only kills mold on contact but is a SURFACTANT, which means it will reside on the surface for a bit and keep spores from reforming. I have one bathroom with no ventilation fan, not sure why. But that ceiling above the shower from the steam/humidity gets black spots and I use MrClean to combat it and only need to like once every few months now where before that was a bi–weekly thing at least. Happy growing

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Thanks! Speaking of bathroom ceiling mold, I just noticed that issue in my upstairs bathroom on part of my ceiling and upper walls, even though I do have a ventilation fan. I have been debating on what to clean it with, usually I use bleach/water solution on mold in my basement but don’t want to use bleach on my painted walls. I’ve dealt with multiple mold issues in my house over the years and bleach has been what I have used, but some things I don’t want to get discolored. I appreciate everyone’s comments and help in this forum!

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This is what we have. VIVOSUN Grow Tent Complete Kit, 48"x48"x80" Growing Tent with VS1000 Led Grow Light 6 Inch 440CFM Inline Fan Carbon Filter and 8ft Ducting Combo We love it and are getting the plants adjusted to it. It is in our basement which is 68-70’s and low humidity right now but with the tent it doesn’t matter. If you click the link it shows everything and You ready don’t have to buy extra equip . Fox Farm FX14049 Liquid Nutrient Trio Soil Formula: Big Bloom, Grow Big, Tiger Bloom (Pack of 3 - 32 oz. bottles)
FoxFarm Ocean Forest Potting Soil Mix Indoor Outdoor for Garden and Plants | Plant Fertilizer | 12 Quart + THCity Stake I say buy the best stuff to get the best weed.

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I already have grow lights which I paid about $104 each so $208 for both of them. So does the tent have to have a specific light or can I just use the ones I already have? I could just buy the other items separately from the looks of it. Also thanks for the advice on the soil! I was wondering about that as well. My friend had given me just regular potting soil and we got lucky our plants grew so well with it and didn’t add extra nutrients but for future grows I figured there was probably better options.

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I would be sure to read ILOVEGM grow guides this helped me tons and use the right soil FFOF Soil is the best and the less you mess with your plants the best they like it. If you buy things piece by piece you will probably pay more total than just buying a grow tent kit, if you use your lights maybe you could start a smaller tent for flowering plants. Read a lot it helped me a lot. Spudeater

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