Idea for a grow box with cooling
 

Why is it that you always want to grow what you can't? Or is it that the really neat orchids are cool growers?

I've been toying with the idea of buying or making some kind of grow chamber with cooling of some kind.

First i thought of using a wine cooler that could be set around 60 degrees and using a fluorescent light through the door.

Then i thought: why not use the same technique that a greenhouse employs? a wet wall and a fan to blow air through it!

At first i thought i would build a box out of wood and acrylic, but ended up with a plastic storage box about 33" x 17 x 14, that cost $13.00 I cut a square out of one end, and another on the other end.
I used evap cooler pad and rigged a pump to circulate water through it. The other end has an ordinary clamp fan that i attached to the wall of the box.

I'm very encouraged by the results so far!! I was able to lower the temp in the box from 74 to 66 degrees, plus the humidity went from 33 to 70%. The orchids should love the gentle air circulation as well.

I will probably put this box in a North window, and add some lights to it.

Below is the link to my photo website showing pics of the set up. Please remember this is still in test mode, there will be improvements to the box!

Cool Grow Box - a photoset on Flickr

Anyone else tried this or have comments on how to make this better? Any hidden risks with this idea?

Peter.

Hey Peter!

Sounds like a great idea. . .can you post pics?

And I'll mull over how to make it better. . .if it even needs improvement!!

My observations: cooling of the tank can be done with fans and keeping the heatfrom outside lights away from tank. Sounds like the "swamp cooler" program is working for you. Go for it. Humidity is a plus with this system. I would go for south window if you have one. You can NEVER have enough light in a tank, in my opinion. As an alternative consider a bank of t5 florescent lights (minimum of 4 tubes).

My concern was mainly in the summer time. With the high cost of air conditioning, my house will normally hit about 82 degrees before i turn it on. I predict a grow box would get to about 85 degrees. If can cool 6-8 degrees, i think the cool growing orchids will be happy!

My next test is to see how much the temps go up with a light fixture!
Peter

The link to pics was added:

Cool Grow Box - a photoset on Flickr

Lights on mine add about 5-7 degrees F. Mine is in basement, and during summer, I run fans to bring outside night air into basement to cool it. During winter that is not so much an issue.

Hi Minicatt,

I've been thinking of a way to create cooled terrarium conditions using an aquarium chiller. These thermoelectric coolers need a way to release heat so the chiller would need to extend through the terrarium wall, it couldn't be placed wholly within the tank. There a company that manufactures a chiller called a nano-probe, it looks like.. a probe. ANyway the cooled end of the probe could sit in a tank of water built within the tank and the heat outlet sits outside the tank.. This probably makes no sense, hers a picture attached...
A gallon of water within the tank could be chilled to 15-20F below ambient room temp, thereby acting as a heat sink for the rest of the tank?

sounds possible, but this seems to be quite a pain to set up? Why not use the evaporative cooling idea?
I have now set some plants in my test case. Came home today, and the inside temp was 9 degrees cooler than room temp, about 66 degrees! So far so good!
Peter.

Peter,

I'm growing Pleuros and Masdes in a terrarium, but it's getting a little too hot. I'm considering trying some Lepanthes and I like your idea. How are things going with the evaporative cooler? Are you using it successfully? Have you modified the original design at all?

Thanks,
Jared

Hi Jared,
Yes I'm still using this case, but have made some modifications. I built a more permanent case, and use the cooler as an attachment.
At first I did not have the cooling unit near an open window which was a mistake. It can get much cooler at night outside vs. inside the room.
I have now moved the cooling unit and have seen improved results!
Here is the latest set of pictures on my flickr account: Updated Cool Growing Orchidarium - a set on Flickr

Pete.