What should winter humidity be in the GH?

16 years ago

I know too wet and you have mold/fungus problems and too dry you have problems with insects/spidermites etc. I understand that air circulation is important. So is there a number you want to hit and if so what should the target zone for winter time humidity be in a greenhouse? Mine is 65 right now but has been in the 80 to 90 range while it was raining and even higher when foggy during the mornings. I have a lot of tropicals; epiphyllums, brugmansia, gardenias, jasmine, bananas, colocasia, citrus and so forth. Thanks!

D

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Comments (6)

orchiddude
16 years ago
It all depends on what is activity growing. Also, the temperature will raise and lower RH. You are not going to be able to make it one number and leave it there, it will go up and down.

I grow orchids and palm trees, I like mine to be around 60% to 100%, it was 95% the other day. You could see steam coming up, it was nice. I love a good hot humid fresh smelling greenhouse.

Right now its 20Â°F outside. 58Â°F in the GH with humidity at 57.
Hope this helps,
Rob
stressbaby
16 years ago
Rootdiggernc, read this post called "Humidity too High" by Greenhouser. I think it will answer your question.

Here is a link that might be useful: Humidity too high
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trigger_m
16 years ago
The only time I've had a problem with mold was before I installed the ceiling fan,and 2 box fans.After That,no mold.Mark
greenhouser
16 years ago
I think the fans did the trick in my GH as well. The humidity is still at 85% in the Rion but the three extra fans did wonders. I don't see any more mold. I noticed today there are hundreds of impatience seedlings under one of the benches! I don't see seed pods but they must be producing seeds.

The smaller HFGH stays around 35 to 40%. I never had a mold problem in there. There's one small fan running 24/7.
stressbaby
16 years ago
You can be sure that if you don't have enough fans, and the humidity is 85% in the middle of the room, there are pockets of 96% RH somewhere in the GH where the botrytis is gettin' happy.

Air circulation does all sorts of beneficial things. Not only does it even out the pockets of high humidity, but it moves the plants around which has been shown to improve disease resistance and make them stronger and stouter.

SB
greenhouser
16 years ago
stressbaby

I agree 100% on this. There wasn't enough air movement with just the two HAF fans running up at the roof on each side. Now with those on the floor and the oscillating one just above the floor.... well all the leaves are moving a little now and the hairy stuff is gone.

What should winter humidity be in the GH?

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orchiddude

stressbaby

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