Grow room issues

Donmikel

Member
Greetings everyone, this looks like an amazing community, and I'm looking to learn alot from you guys, and hopefully teach you some things as well.

A little background I live in Jamaica, and over the last year and a half, I started growing weed for myself and my friends. I usually grow outdoors, but somewhat recently i moved, and I still do grow outdoors, but here where I am now outdoors are full of bugs and mold (high humidity)for my plants. A problem I never had before. Because of this I decided to grow indoors and I already had some grow lights. And I am totally against pesticides. I've tried neem-x a derivative of neem oil, but it doesn't work imo.
I explained all of that because people say your in Jamaica, why not use the sun. And I still do as I have 5 plants outdoors growing (which is the limit they allow)

Now my issue is,
Because it's a shed away from the main house, I had to find away to provide it with power, and my solution was to use solar. And I do plan to expand the number of panels and batteries in the future, but for now.
My humidity in the room, is about 50-60% when the sun is out sometimes even in the 40s. But at night it avg between 70-90. The other day it was raining , and that night it went to 95.
I do have a dehumidifier but during the days it's not in use much as the relative humidity is ok. But at night I have a big issues. I cannot run the dehumidifier because it kills the batteries fast (remember solar powered). And this results in the dehumidifier turns off, and so do the fans and grow lights. Which doesn't make sense as the humidity will quickly rise again and no power.
If I leave the dehumidifier off, the lights stay on. And everything else works but the humidity is high, which I thought that can't be so bad. But it is. Its terrible. The plants I have indoor were planted the same time as the ones outdoors and it's no comparison. The ones outdoors look healthier, bigger and are stronger than the ones indoors. So I need to find away to lower the relative humidity naturally, so that the dehumidifier won't have to work as hard at nights and hopefully keep the lights on.

I'm open to all suggestions. I tried buying a ventilation fan which only seems to drop the humidity a point or two. I noticed when I turn off the oscillating fans at night the humidity decreases about 5 points. So I started turning them off.

If I was to seal the room all together and then use a fan to intake air, would that be better.

Also to be fair, the temp in the room is also high in the days around 93F but that's a easy solution, get a ac unit, but I think I want to fix humidity before I fix the heat. Or is the heat the reason why my plants can't grow as well (which I doubt because outside is hotter than inside and they grow better outside, but who nows?) (Because outside just as humid too imo) or is it even the grow lights, idk. (I have solar system 550 (blue 99, white 99, red 30)) and 3 roleandro 2*200w cob as supplement lights.
So if we do the math that's like 1750w of light, so I doubt the it is lights, but something if preventing my plants from growing.




I also added pics of the shed. It goes all around with the mesh at the top and ply and concrete below.
The oscillating fan takes the air from outside disperse it around the room, and there is another oscillating fan not shown that stands on the ground.
 

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OldMedUser

Well-Known Member
With high RH you want the circulation fans going 24/7. Static air conditions are perfect for molds and fungi to take hold when it's so moist.

Can't you just run the dehuey when the lights are off? The RH goes up as the temp goes down because it's relative to the temp. Same amount of water in the air but relative to the temp reads as higher.

Water the plants when the lights first come on so the top of the soil can dry out a bit before their night to help reduce RH. I was watering from the bottom a few weeks ago to keep the top dry and that helped a bit. RH is still a little higher than I like but at 52 days 12/12 there's no sign of bud rot. Knock wood!

:peace:
 

Renfro

Well-Known Member
Seems like a greenhouse would be a simpler solution.

If I was to seal the room all together and then use a fan to intake air, would that be better.
Having more power would be better. Trying to grow indoors using a battery bank and solar cells is going to cost a fortune to do it right. You will need a large battery bank and thats not cheap and it needs periodic replacement.
 

Renfro

Well-Known Member
You think the heat shut them down more than the humidity?
I've been looking around for CO2 but haven't found it here yet.
I mean just bringing air to get outside levels of CO2. If you don't bring in fresh air for CO2 the plants will use up whats in there and then shut down.
 

Renfro

Well-Known Member
Humidity didn't shut them down at all, the only problems with humidity is mold / mildew. Check out VPD charts, the warmer you are the higher the RH% needs to be.

It's probably either heat or CO2 unless they are rootbound.
 

Donmikel

Member
Seems like a greenhouse would be a simpler solution.


Having more power would be better. Trying to grow indoors using a battery bank and solar cells is going to cost a fortune to do it right. You will need a large battery bank and thats not cheap and it needs periodic replacement.
Honestly I thought it would have been more simple as well. Yes, solar is turning out to be an expensive upfront option. But I got a really good deal on the batteries. I have 16 375ah batteries. But only 8 connected to the system now, as need more panels in order to charge the rest of batteries. More power is coming soon. But still trying to find a way to combat humidity naturally.
 

Donmikel

Member
Humidity didn't shut them down at all, the only problems with humidity is mold / mildew. Check out VPD charts, the warmer you are the higher the RH% needs to be.

It's probably either heat or CO2 unless they are rootbound.
There shouldn't be root bound, as I use the air pruning pots. But thanks for the insight.
 

Nizza

Well-Known Member
a small improvement on further light investments: try going with leds that don't need a fan on them, this is consuming more power

an example is a quantum board LED by HLG https://horticulturelightinggroup.com/collections/quantum-boards
you aren't going to run the LED's at as much of a draw but also won't have to pay for the fan running that cools them

as for dehumidification, I know of a product called damp-rid but not sure if the chemicals are bad for plants
after looking into this further it is non-toxic but you dont want to get the stuff on you. Also, you would want to drain the water it pulls from the air out instead of letting the removed water sit at the bottom of a bucket harboring mold/mildew
you could also reduce vapors by painting the cement, and then using plastic thick plastic to create a vapor barrier on the floor. you may also want to encapsulate the whole room so its air tight and then vapor barrier the whole thing. This way your dehumidification would be more effective
 
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OldMedUser

Well-Known Member
Humidity didn't shut them down at all, the only problems with humidity is mold / mildew. Check out VPD charts, the warmer you are the higher the RH% needs to be.

It's probably either heat or CO2 unless they are rootbound.
If the humidity is too high that will slow growth to a crawl as well. The stomata won't be able to get rid of water, (transpire), and shuts things down.

I find the VPD charts are a tad high imo. Like a sauna in my grow room a month ago and it was still 5 - 10% lower than the charts.

When you outside RH is high the only thing you can do is dry the air before it goes into the grow space. Seal the room and have all the incoming air pass thru the dehuey before getting in.

Otherwise you need to run a sealed room with CO2 and something like a dual-hose portable air conditioner to cool and dry the air like I want to set up but for me it's to keep my RH up as it's dry as a popcorn fart here 10 months of the year in northern Alberta. Lack of power is going to hinder you there tho.

Good luck!

:peace:
 

DailyBlastin

Well-Known Member
Hey there. Ive read the OP but not all the replies so i apologize if someone else already covered this but here goes!

First things first, your shed doesn't appear to be insulated at all, that should be one of the first things you want to take care of, insulate the walls and ceiling, then drywall the interior so that you can paint it white. white will give you better reflective surface and make the most of your lights! While fixing up your shed you may also want to wrap the exterior (you'd have to pull off the siding if there is any) in a moisture barrier or WRB (then replace or add siding over that) this will help to keep moisture out of the enclosure. From there i would go ahead and get a small a/c unit that you can install in the wall of the shed, this will not only regulate your temperature obviously, but will also help the RH issues your having as air conditioning an enclosed space will suck the humidity out of it with ease (albeit you're in an extremely high humidity climate so the dehumidification effect of the a/c may not be as great for you as it is in other areas of the world, nonetheless it will help more than it will hurt!). Being that you're on solar power i would recommend making the fore-mentioned upgrades to your shed and simply running a long extension cord to power the a/c (and the dehumidy if still needed) and let the solar power work your lights and fans until you can add more panels/batteries to power the whole thing.
 
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