I bet your days need some heat too! What do I know, I am just a southerner. I can only imagine.

If it's propane or kerosene make sure it's exhaust is vented outside. And kerosene stinks!

how hard would it be to install a wood stove? that is how i would heat my greenhouse. wood is pretty cheap, and renewable, and smells awesome. can you tell i heat my home with a wood stove. i do not know about a greenhouse but have heard that those eden pure heaters are pretty cheap also, if you choose electric?

Doug

this is a little greenhouse, I'm not making money off of it. Just a place to keep my plants from freezing (and not use up all of my living space)

the most ideal thing would be a pellet stove like I use indoors, but I dont have a place for it out there nor the money to buy one. I'm talking about cheap heat during the winter, that would be simple.
The kerosene heater I'm looking at is made for indoor use.
Yes Mara, the days get cold here too, but some winters are snowier and colder than others.

Hi -

I am using a small ceramic heater in my hobby greenhouse (6x12), but I do not plants to keep my plant in there throughout the winter. I just put it on at this time of year to extend the season a bit and keep temps from dropping too low (below 50) until I get most of my plants indoors or garaged for the winter.

How big is the greenhouse you are planning to heat? How will you get inside it when the 'snows' come (I live in MA)?

Tom

Doug's idea is worthwhile, Sherry - you've got a few source that can be maximized with the proper wood and efficient burners with distributive pipes. One think you might consider is improving, if possible, the upper reaches of the greenhouse to trap the heat more permanently during the night when it's produced - sheets of polyenthele, as long as they're sufficiently away from the heat source / pipes, should improve the ambient heat to where a Raphionacme flanaganii would never contemplate going into dormancy and an Adenium arqbicum hybrid might keep all of its leaves, too..

Another thing is the base of your greenhouse - the more layers between the ground, the better, but up to a point, however - a ziggurat is rather self-defeating in terms of numbers of plants.

I'd love to be there to help you with the greenhouse - you could even make me tea Mother during our breaks. I could learn a lot from you.

Tom, I think my gh is around 9feet by 16 feet, and the roof slopes (so the snow can slide right off :-) and is about 9 or 10ft at top of slope down to 6 or so at bottom.)

the flooring is rocks over plastic. I plan on putting 'blue foam board' on the few places I can, plus bubble wrap or plastic sheeting over the windows.
Jeff, insulating or whatever the roof area is a good idea- I was thinking of using more foam board or something cheap to put over the top of the gh (inside of the roof area.)
Guess I'd better 'think' quickly- just heard that Monday night will be 32 degrees F. The guy who built my gh didn't know about gh's, but I am happy enough with it.
Yes, would LOVE a woodburning stove, but I dont have one, nor the money to buy one or install. Plus, not sure if there would be a way to vent it. That kind of thinking is for next winter, when I have more experience with (NOT) losing plants that I love. This is first winter I will actually try to use it thru winter. Last fall it was finished at end of November, so I used it for a few weeks for cople tomato plants, pepper plant.
These are all good suggestions.
The guy who built it last year has repeatedly apologized because he didn't know about gh's. . . . I'm not complaining, I paid for labor (he had some left over building materials that he gave me ...and it was something he'd promised to do for me a few years ago when my dh died- he knew my dh) and I had some left overs too.
Jeff, I do plan on going out there to drink tea or coffee on the cold bleak days of winter. You are welcome to come out and sip some with me. My favorite chair is out there already.
There isn't time for it now, nor money, but I will keep my eyes out for wood or pellet stove from 'UncleHenrys' for next year and keep researching this kerosene indoor heater.
And also insulating the place.
Thanks you guys for your input! Any of you are welcome to come to my gh (if it's in winter, bring your snowshoes, I think it might be a hard winter)

Sherry, I have a 8' x 15' freestanding GH. I am in the SE Michigan area and like you, must heat day/night til next May. Out of laziness I have never wrapped my GH in plastic or clear swimming pool covers or bubble wrap. My GH has been up since May 2007. I have heated it with the same 20T Btu natural gas heater for all of this time and have a 15T Btu backup electric heater. My gas cost is about 3~5%. The natural gas heater is meant to be used as a space heater indoors and is not vented which works for me and has a thermostatically controlled fan. They cost about $260.00 at any big box store. Of course, if you don't have a natural gas supply, this won't work.

thanks Doc, I'll check it out.

sherryinmaine, I'd like to throw in my 2 cents... The type of heater that bikerdoc5968 is talking about is the best way to go. These type of heaters are also available that use propane. This is only my opinion but stay way from kerosene heaters. Going that route is only asking for trouble. Mike

Sorry, I forgot to mention the propane models but you're always going out for a new tank unless you have one of those behemoth tanks. Also, these have a safety so if it tips over or the pilot goes out the gas shuts off. I screw mine to the floor.

I appreciate everyone's input . . .

Mike, why stay away from kero?

I am on a 'cheapo' budget. I dont have lots to spend (and also dont want to lose what I've spent on plants!)

Think I've received some good suggestions, and am checking out diff. kinds of heating ...
Gotta buy sumpin soon . . . .talk to some of the big box guys, and surprised that it seems to be a circle of 'bla bla'--- they start with 'blah blah' and end with 'blah blah' . . . .In other words, they dont know alot about what they're selling . . . .

I don't know if you have "Tractor Supply " up there. They always had a better line of heaters for a better price. But , again , this is in Texas and not Maine. I do not know how far a field this chain goes. It caters to more rural areas and needs.

Mara, I just might check one out . . . there's one on outskirts of Bangor, a little bit away from me.

I'll look online, anyway, and see what they are offering.
I have used them for dog worming supplies and dog toys . . . Also slobbered over boots they were offering . . (ah, Tractor Supply, tres chic . . . )

Avoid electric heaters if possible. They're expensive. I use an electric heater for a small GH and my utility bill goes way up when it runs alot. The other GH's run on propane and it's much less expensive. If natural gas is an option I'd go for that. I have a friend that heats her commercial size GH with wood. It works great and is very inexpensive but you need to install a really good ventillation system.

I would stay away from kerosene because the heaters put out carbon dioxide, carbon monoxide and sulfur dioxide into the air. Not good for you or your plants and superb ventilation would be required. The odor from the fuel is strong and an open flame is a big fire hazard.

You might also want to increase the thermal mass in the GH. Some people use buckets or trash cans painted black and filled with water. The thermal mass absorbs heat during the day and releases it at night.

yes nil13, I have read about that thermal thing . . .nice idea if you live where the sun is strong enough to warm up big barrels of water during a winter day.
Guess I'll be bonked anyway I go . . . electric bill heightens in winter,(use those elec heaters in kid's room & bathroom upstairs, early in winter mornings) kerosene stinks, flame, etc.

No natural gas nearby.
Thinking about talking to local fuel oil place, they have propane tank on my property that runs the generator when there is an outage. If too expensive, it's a no go . . . .

Yes, those propane tanks that you use on barbeques are handy, but yes it's hard to keep track when they run out . . .
We'll see.
Appreciate all of your input.