Regulating Humidity in GH in Winter - Orchid Board

Ranchnanny · #1 (**permalink**) 01-20-2009, 12:53 AM

OK I have my new greenhouse up and running with 2 fans, heater and water feature for humidity. In an 8 x 7.5 GH what should the humidity be during the day and evening. My GH seems to be to dry 30 to 40 % humidity. Until I move a misting system in there I have been hand misting several times a day. Doesn't seem to be enough.

Would love to hear some suggestions

Sheridan

Ethan · #2 (**permalink**) 01-20-2009, 08:11 AM

Hi, Sheridan!

In my experience, there seem to be quite a few factors that go into the humidity in my greenhouse.

1. How many plants do you have in there? The more plants, the higher the humidity will be.

2. Outside temperature. The colder it is outside, the lower my humidity gets inside - mostly due to the heater running more and drying out the air.

3. How much sunshine? In the winter, on cloudy days my humidity is lower due to the heater running. Sunny days, it's higher due to the heater not running as much. Then of course, it's the exact opposite in the summer.

4. What's the base made out of? I have a concrete floor and a concrete kneewall. If you have concrete, you can always spray it with water. Concrete will soak up water and help raise the overall humidity.

So far this winter my humidity has been pretty steady at the 60-80% range and I do nothing extra - just the things I mentioned above. However, it's been really cold here lately -10F to 20F. Seems when it's below 30F my humidity will only range from 40-60%.

One other thing I wanted to mention. I noticed that my high humidity levels did not maintain themselves until 6months to a year after the g/h was built. Seems like it just needed to get it's own little eco-system established which will take awhile.

Hope this info helps!

mojomick · #3 (**permalink**) 01-20-2009, 10:59 AM

Ranchnanny, Ethan said it well. My greenhouse is 9 months old now and is maintaining the humidity between 70 and 80%. When I water of course, it stays on the 80% side. As the week progresses, and the heat keeps running, it may go down to 65. During the fall and early winter, I had trouble getting the humidity down. I did find that I started to get some fungus and bugs when the humidity was higher and the temps were in the 50's. I raised the thermostat to 60 and it has helped with that problem. I am really watching the scale. I never had bug problems until I built the greenhouse and only when winter appeared. I'm not having to water as often of course, but do find that I still need to water the semihydroponic plants at least every week. I'm so happy with the spikes I am getting. I think you will find that your plants start responding within a month or two of going into the greenhouse. I am so happy for you. I can't believe I didn't do this years ago. I encourage everyone to build a gh. It is so much easier than dragging all those plants to the kitchen sink every week and boy do they like the new environment. Happy growing. ps. I hope you are well and not having to deal with too much snow. It's all gone here, but still cold. Betty

Ranchnanny · #4 (**permalink**) 01-20-2009, 12:13 PM

Thanks Ethan for the specific comments which are a huge help.
Betty, the snow is all gone here but its still so cold dropping down into low 20's at night and for the last few days not above 27 during the day.

Can't wait for spring.
I love the GH just wish it could have been larger but maybe I can get a larger one at a later day

.
The floor of the GH is gravel with pavers down the middle. I am seeing results already with my Equistris Zuma Beach. The mother had a spike with a keiki at the end of the spike and when that had long enough roots I cut it off. Now the baby is well rooted and putting up a spike and so is the mother.

Having to haul water in jugs to the GH due to the fact that my outside water system is shut down for the winter. Things will be easier when I can turn that back on.

Thanks Sheridan

Ross · #5 (**permalink**) 01-20-2009, 01:50 PM

Sheridan, my only greenhouse was in Grants Pass (so consider this in my comments). During the winter it was no problem for me with all the rain. Humidity stayed very high. But when I was in K Falls, humidity went down through the floor! I think you are fighting a losing battle without a fogger or active humidifier, etc. Can you get a floor humidifier meant for the house and run that till you settle on a misting system? A misting system isn't the best thing for a greenhouse as it affects the heaters (that's how I lost my oil stove in my greenhouse and what ended my greenhouse adventure in G.P.) I suspect if I were more creative at the time, I would have installed the fog nozzles under the benches or at least below the top of the oil stove. Water and fuel oil don't mix! Water and thermostats fair even worse

Ranchnanny · #6 (**permalink**) 01-20-2009, 06:34 PM

Hi Ross thanks for the input. I am still going to install the misting system for use in the summer months and I guess just go out there several times a day and hand mist. I do have a water feature in the middle of the one bench to help with humidity. I will have to check out a humidifier.
I love my little Orchid Hut....

Sheridan

Ethan · #7 (**permalink**) 01-21-2009, 08:40 AM

I'm glad you're seeing improvement in your babies, Sheridan! I'll never forget how exciting it was to see mine so happy after their move. As Betty said, you soon wonder why you didn't do it years ago!

Ross has some good points - I would probably opt for a home humidifier until your g/h gets established. I'm not sure what your ventiliation system is like, but for me I have a harder time getting humidity in the summer because the exhaust fan is running so much. I wish I had a misting system. Luckily summers are very humid in ohio!

mojomick · #8 (**permalink**) 01-21-2009, 11:09 AM

Sheridan, I have my misters under the benches and they are connected to a humidistat. It can be adjusted for the % of humidity you desire. It has not run since fall when the humidity sky rocketed with the cooler weather. I have it set for 60 % in the summer. I like the idea of it being under the benches, then I don't have to worry about water in the leaves at night. In the winter, just the once a week watering seems to keep the humidity high. NO problem with heaters getting wet this way. Betty

canadianorchid · #9 (**permalink**) 01-23-2009, 12:47 AM

I'm new to this site (great info!), but here is my input re the humidity. I found that since I added a small humidifier my orchids are getting some really nice-looking roots. The humidity has been as low as 40 without it. I am wondering if anyone can recommend a good brand for a humidifier, as mine just quit on me & I've only had it since last August.

Ranchnanny · #10 (**permalink**) 01-23-2009, 01:13 AM

I have decieded to add a misting system to the GH. I will be moving the HerpMist system I have in my Orchidarium to the GH. I have plenty of tubing so I went to HD and purchased quick connecters, elbows and t's to extend the system. BUT.... the only thing they didn't have were the mist heads

. They don't carry the mist heads

they said so off the Lowe's it was the same thing there.

They carry everything to put a system together but no mist heads (plastic). Geeeez!!!

Without mist heads the system isn't much use

SOOOOOOOOOOOO! Mist King here I come ordered 7 L shaped mist heads.

Will post pics once its set up.

Sheridan