Low humidity, is this an big issue?

Question from a fellow grower:

I would like a question to be answered? I live in a cold climate. Its 12 outside right now! I am growing indoors. I have a grow tent in a shed outside. I can keep it any temp I want, humidity is very low. Lighting is very good. 2- 500w LEDs. My question is will low humidity effect my plants? I have a cool air humidifier, but according to my hygrometer the humidity does not seem to rise. I have plans and glasses of water everywhere trying to get to 60%. I can only get to 30%.

I am in the same place it is very hard to get 40% humidity with the cold dry weather i spray my plants with water and leave water in a bowl to my exhaust system takes alot out even with a humidifier its great for flowering but it’s o.k. for veg but not optimal but they will still grow.

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Same issue it’s cold here and basement I have to try pretty hard to get the humidity to stay up there. I have to use a small heater so it dries up the air quick.

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Same problem here. I use a bucket with rolled up paper towels in it. I filled a 1 gallon bucket about a 1/4 full. I lean the paper towels on the side of the bucket, put my passive intake pipe into the bucket and cover with plastic wrap. I make sure to leave a small opening for fresh air. That has kept my tent 48 to 56% humidity. Before this my humidity was at 29%. It’s made a big difference. I’ve tried a lot of different methods but this on works the best.


That’s interesting, makes sense though and it keeps the other room from getting more humid. That’s my issue it’s my basement so more humidity is bad if it’s too much

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I love that!!! Same principle as a standard furnace humidifier. Gotta love Cannabis Cultivation Engineering!!!


Trial run. I’ll beef it up quite a bit for next winter. My big exhaust fan isn’t running right now. I’m using two 4 inch fans to move air. I also plan on getting a humidity sensor to run the big exhaust only when I need to. No more carbon filter for me. My last batch smelled so wonderful the carbon filter couldn’t keep up. I’ll be venting outside from now on.

in the veg stage u want 50-70% RH, but 20-70% is okay most of the time,
in flower 20-50% is okay, 40-50% would be great,

do not sweat the RH too much, keep in the acceptable ranges and u will be fine.!


great idea @shindig153 same problems here.

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