We built our 20 by 40 foot greenhouse last year and now we have decided to heat it for the winter so we can grow food in it and start our seedlings even earlier. We had a greenhouse years ago that we heated with propane heaters and were very satisfied with it so figure we might as well do the same thing here. We have a back up generator rigged up so in the event of a power outage we could still heat the greenhouse. I would like to hear from any of you with some experience/knowledge on heaters as to what might be the better brands to stick to and any pros and cons when picking one out. I don't remember which brand our old one was.

-- Colleen (pyramidgreatdanes@erols.com), July 16, 2001

Answers

Hi Colleen,

I have a friend who built an innovative corn-fired heater (that's certified also to burn wheat or rye) about ten years ago.

He's had a location on the internet for a while and I've been looking for ways to get him found by more search engines. While doing so I've found a number of locations where other corn-fired heaters are shown.

I heard that greenhouse keepers often inject extra levels of carbon dioxide into their greenhouses to produce better plant results and some consultation in a local area with a concentration of greenhouses over the weekend confirmed that.

The corn heaters must push quantities of air through their fire or it won't burn, which produces almost complete combustion. There are low levels of pollutants in their exhaust, most of it carbon dioxide. None of the products of combustion are noxious, I'm told.

I think that many find that the cost of heating with propane is quite high (using electricity being higher, usually, I think).

Should you choose to use a corn-fired heater, I think that you'd find that shooting some of the exhaust into the greenhouse would be advantageous.

You might be able to find a used one, though with the recent price increases for most fuels, many are using them to find lower costs of heating, so it's probable that few will be for sale at present.

I heard of one on the internet the other day, and know of another in this area (north of Lake Erie).

Good wishes in your quest.

Ed Baker

-- Ed Baker (eddbaker@yahoo.com), July 17, 2001.

My first greenhouse I ran a propane heater, looked like a torpedo and didn't vent it assuming that the small amount of airflow would be enough. I actually was poisoning my plants without realizing it. Young seedlings are especially susceptible. Make sure you vent and the corn burning heater sounds great for carbon dioxide, plants love carbon dioxide! Too much would not be good for us however.

-- Cindy Martin (mail@chefsgarden.com), October 03, 2001.