I recently run into a wall. A wall of humidity, that i can´t really fight.
The situation is as follows:
About 120x120cm (4x4) in a cellar. 3 walls are stone (dry), one is the “door” made up of a cut down grow tent. Light is 300w led spyderfarmer or mars hydro (its literally the same), the house is just next to a river and we are pulling the air from inside the house, from pretty much the warmest place inside.
Problem: When the intake air is for example 70% RH, we get 73% RH inside. Which is good performance in my book. But thats a good day.
Usually humidity ranged around 75-84% inside. Temperature 19-24°C. Shit grew like hell. We reduced the leaf area by removing 50% of all plant matter. 2 buckets full and 1/3 of the plants on top. We doubled the exhaust, we added an oscillating fan, we eliminated the intake filtering.
We repeated the reduction of evaporating area a couple of days later a second time. Another bucket full.
Now we got it down to below 75% at all times, but thats still too high. Because the air outside is just so humid next to the river.
The strain is Kritikal Bilbo (OG from Bilbao sources).
Would that work?!
I don´t know what i am missing, but short of adding a dehumidifier (which does not seem to be an option…) i am out of ideas.
You can take out the little chamber they have to collect water and put a hose(that comes with it) into a 5 gallon bucket…you will probably have to empty it like everyday or other day, but it will get you down to where you need to be
Well, he is like 600 bucks in to that adventure and now i am not only telling him that his buds are going to rot, after i told him he had to rip out 1/3 of the plants, i am telling him to spend another 150 and double his electricity bill to avert it.
My only question here is, if it is possible to have plants in bloom at 75% RH and not end up in complete disaster. Because i don´t know. I grow outdoors or in small tents in dry houses.
I feel somewhat responsible for the situation though, since i helped him setting it up and didn´t foresee the problems that are the problems right now.
If a dehumidifier is not an option, I’d raise the temps up to 29c or so. The plants will appreciate it with the LEDs anyways, and the RH will be closer to appropriate.
Possible? Sure, depending on strain and other factors.
If it’s a modern strain with chunky buds, you’ll ,likely see bud rot or mold. Somebody will say they’ve done it, and I have no doubt that’s true. Maybe you’ll be the next to pull it off, who knows.
If you cannot control the environment then an OG will rot. You will need something resistant to high relative humidity. Try Thai or Hawaiian. COPA genetics has good resistance usually since he breeds outdoors in Maine.
So I battle humidity here in Louisiana, outdoor humidity typically peaks around 90+ percent mid day.
I have a roughly 10 x 10 shed, running both an room air conditioner (vented to the outside) and a dehumidifier (2000 sq ft model) set to run constantly.
On a good day (low outside humidity) this gets me low 60% rh. On days like today where the outside humidity is over 90, mid 70% is more normal.
I make sure and keep the plants defoliated, especially the centers, and also run a large box fan at medium setting constantly. if I turn that fan off, or let the foilage get to thick, i have had problems.
But, with those preventative measures, have had some grows that made me very happy.
that said, your already so far into it, get more fan airflow, do the best you can to reduce the humidity (maybe a friend has a dehumidifier you can borrow?) defoliate, defoliate, and then defoliate some more… And I will be happy to hope you are blessed with some big fat rot free nugs…
With all the above said, as encouragement… I strongly prefer to grow in late fall - into winter - and early spring… because humidity and temps are so much easier for me to control.
Its more than likely going to have issues, and like others said, its going to be easiest just to get a dehumidifier…
Or like others said, choose sativa genetics(which will take longer) or grow in winter only
Hes already that much $ in, a moldy harvest is going to be more upsetting than spending the $ on a dehumidifier…plus they can use it for a long time after, its not a one and done
Its not going.to double his bill…the dehumidifier has a setting to only go to what you want it to, you can place directly in tent…mine costs less than 1$ a day to run if i ran it all day
My humidity stays close to 70%. Some strains will do better than others. I try to have lots of airflow. You could top the plants and have smaller buds verses one main cola.
I would suggest training your plants to have many branches, to cut down on the size of the buds, defoliate, and lots of air flow. Don’t flower in the summer, and I would also suggest a dehumidifier.
yeah solid advice there, it really is pushing the envelope of what the plants are willing to grow in. But sometimes you just gotta do the best you can, and either eke out a win, or learn from a loss.
super airflow seems to overcome higher humidity. I got bud rot only once when i had the hugest buds and it fell into the corner of a tent. it wasn’t getting any airflow from the fan. made sense. I think golfball/og type buds are the best for high humidity. allows for a lot of air flow and not a lot of deep microenvironments. some of the super fluffy stuff is ok, but if it’s hybrid it can dense out and get moldy.
Here’s what I would do first. Buy two 6 inch duct fans. Run a duct line for intake air from the least humid part of your house or from outside.
Then run the exhaust out of your tent into the house or outside
By having a intake and outtake you are bypassing all of the moist air in your basement. No dehumidifier needed.
Assuming your outside air or house air is within 40-60% humidity
Also if you have raw stone walls in your tent you need to seal them off. Use a nice house wrap like tyvek and create an air tight seal to block out that
Defoliate all the fan leaf for a first round of training Immediately. Then go back and remove all of the leaf that block any bud sites. This will be the only way you can lower relative humidity in your environment without using more power. If you cannot run a dehumidifier Then your only other option is to exhaust more air outside. You will need a constant flow of fresh air circulating through an exhausting outside for your best chance. Cheers !!!
We already suck in the air from above the basement, but it is still too humid. The walls in the basement are dry. The problem is that all the air inside and outside the house is too humid.
Defoliating has been done 3 times already.
Yesterday we immediately bought a dehumidifier, but we still have to build the duct work so it circulates the air inside the grow area since it does not fit inside itself. Should be completed some time next week, after the ducts and fittings arrive.
First test run was promising and i think overall the power consumption won´t be too bad.
Yeah, we live about 150 yards from a river here and if I didn’t have dehumidifiers I’d basically be a mold farmer. You can’t always control your location but you can do a lot to control the design of your grow.
Best one can do is have the right phenos. Diesel/sour diesel hold up well for me. I let mother nature select for me.I have two early Iranian cross phenos that were runts. The rain/humidity rotted the others away meanwhile the runts survived and started thriving after.
And I will be happy to hope you are blessed with some big fat rot free nugs…