Humidity vs. CO2

zeitate

Member
I have a dilemma guys and I think you can help. I'll try to be as descriptive as possible.

Here is my grow journal: https://www.rollitup.org/t/zeitates-grows.817623/

I have read that you should have a relative humidity of 45-50% when the plants are flowering, and to go as low as possible in the last 2 weeks of flowering. This is to prevent mold and "When the humidity is high, cannabis plants use their leaves to absorb moisture from the air which causes them to drink less water from their roots."

My plants are currently in their second week of flowering. My current humidity is about 65-70% when lamps are turned on and 75-80% when lamps are turned off. I have this humidity level because my intake fan brings air into my grow room from an underground basement where the humidity is at 95% and air temperature is about 5°C (I do not have any other possibility from where to bring air into the grow area; let's just say it's a complicated situation).

I can turn the intake off and keep only the outtake on, and that will bring the humidity to a more adequate level of about 50% and even lower. But, the downside is my CO2 level will drop considerably, and we all know how important CO2 is for bud growth.

So, my question is this:

Which is more important when it comes to final yield of plants, the air humidity to be kept at 45-50% or to have a constant air flow/CO2? Air humidity or CO2?
 

Thecouchlock

Well-Known Member
More importantly having your humidity that high is going to mold the inside of your buds and then you'll break one off to smoke and see the nasty ass gray mold.
 

zeitate

Member
Yes, that's what I'm most afraid of. Better to have lower CO2 levels and a lower yield than to risk mildew and mold and ruin the whole crop.
 
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