I intend to make a box for cool growing plants.
To explain my need, there are a lot of plants I grow that grow in climates where it is quite cold. Particularly at nights. In contrast, here the night temperatures drop under 20C for maybe a month or so.
While my larger plan is to acclimatize and grow these highlanders “normally” in our climate, acclimatizing for some does not happen fast enough and they die. Or they die when our summer hits.
I don’t intend to create “perfect” conditions for them (since the idea IS to acclimatize them), but I need some way to boost them through hard times.
I am thinking of several options.
This is a simple idea. A thermocol box with a dual peltier cooler on one side. Because the peltier tends to dry air a bit as well as cause condensation, something to collect the condensation and put it right back in the air with a fogger. Earthen pots for the plants inside, so they get cooled by evaporative cooling from the peltier breeze (and the somewhat inefficient cooling gets boosted a bit)
The top of the thermocol box, when growing large plants, will have a mosquito screen with holes for the pots/plants to come up through. The mosquito screen will be covered with live sphagnum moss (which also loves the cool and is also a fantastic evaporative cooler in its own right.
When there are small plants in the box, the top will be covered with (removable) glass. Mainly covered at night and open in day (or an unintended solar cooker…)
There is a controller I have that should switch the peltier on/off based on temperature. I want the cooling to come on if day temps cross 32 and stop after it drops under 30 and start at night if temperatures are above 25 and stop at 20.
This may not be perfect. The peltier may not be as effective as I imagine. Or it may become such a power hog that I’ll prefer dead plants anyway. lol
Hard to say, before I find out.
I have a water cooling module to replace the fan on the cool side of the peltier. Can use it for periodic drip irrigation of plants that need cool roots. No construction involved, simpler to implement probably and may be better if the grow chamber turns out to be too much for the tech.
Also, I’m coming to the HBSCE tomorrow and bringing all this along to MAKE. Be there if you want to see/make it happen.
Yes this is short notice…