Carolina Gardening: Time For A Rain Dance - Part 2, 1 by Xeramtheum

Xeramtheum wrote:
There might be a problem with that in that polyethylene like polycarbonate gives off poisonous gasses when heated. I don't know how hot halide lamps get, but you might run into a melting problem as well.

I learned with my greenhouse that you can keep it at "don't freeze" temps, and plants do very well. In winter I keep my greenhouse at 36 - 38 at night and haven't yet had any adverse effects on the plants inside. I use a plain old oscillating space heater and a portable thermostat and in the 3 years I've been using it, I haven't lost a plant. What might be a better and gentler heat source is one of those oil-filled radiator heaters. Coupled with a portable thermostat:

http://store.kkontrols.com/

and using fluorescents, I think it would be safer and cheaper in the long run. I also use passive solar heating in the form of 2ltr bottles painted black and filled with water, they collect heat in the day and release it at night. For plants I want to keep growing (albeit slowly) rather than go into stasis, i'll place plants directly on top of the bottles.

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