So, I was gifted with a greenhouse..........

(Also, sorry if this is in the wrong place.)

We have a suburban lot, and we recently were gifted with a fairly large greenhouse (at least to a non-commercial grower) of 12 by 10 feet, and side walls of 8 feet. It's going to be put up on our back patio (which we really do not use, at all) which is cement, about 4 feet from the door. It's fairly sheltered from the prevailing winds by the house. We're in zone 7, and I'd like to grow dwarf lemons and mangoes (ideally) as well as things that could use a little more heat, like basil and tomatoes. I realize that I may just have to bring in the lemons and mangoes during the coldest parts of winter.

But, I'm looking for advice and ideas on how to keep the greenhouse above 40 degrees (that's apparently what mangoes are hardy to) during the winter. We're in zone 7, and usually our winter lows stick around on the high end of the 20s, except for about a week each year, when they drop down to below 10 degrees. I'm intending to have a 100 to 200 gallon pond in there and use buckets filled with water to support shelving, and I'm considering having the chickens in there during the winter and insulating the back wall. I've though of having a rocket stove in there, and I've been advised to look into propane heaters. I've even thought about hooking it up the the house like a passive solar heater. Maybe I'll just stoke a little fire in the center, well away from anything flammable. I don't know, that's why I'm asking you, and hoping for first had experience and advice.

I have yet to set it up; we're going to get started on that this week, so I'm gathering ideas now.


If anybody is interested in more details, here's the <a href="http://www.harborfreight.com/10-ft-x-12-ft-greenhouse-with-4-vents-93358.html<br /> ">website of the place it was bought from, and here's some guy's modifications to make it better.

There are also multiple threads on the GardenWeb forums regarding the Harbor Freight greenhouses.

Dunno about mangoes, but meyer lemons will be doable in your greenhouse. The very rough rule of thumb in greenhouses is that each additional layer "moves" your greenhouse about a zone further south. So you could make a plastic tent for your lemon inside the greenhouse and your lemon will be growing in at least zone 8 for the winter.

The lemon will be triggered to bloom during the short days of winter. How a tropical mango will react to the temperate zone variation in day length, I don't know. It isn't just low temperatures that govern where a plant will be productive.

Thanks for the tip about GardenWeb, I hadn't thought to search them.

I have a Eureka Lemon, which hasn't been doing too well, but I'm hopeful that the greenhouse will give it a boost. I've read that lemons and limes are the best citrus to grow in cooler climates, so I'm considering finding a lime.

I've just begun to toy around with the idea of a mango, so I'm not too attached to it. I do, however, use a lot of lemons, so if I can get the Eureka (or maybe a couple Eurekas) to grow well, I would be well pleased. If not, I'll just have to content myself with loads of basil and tomatoes.

our little greenhouse is a bit smaller but you can keep it from freezing with candles..you can use up all those stubs..

suppose you could use heat lamps as well.

also you can divide the greenhouse by sectioning it off in winter with heavy plastic or bubble wrap into smaller rooms..or even use coldframes inside..and keep the very tender plants super insualted that way.

I suppose wrapping the trees in bubble wrap and closing off the top and bottom would keep them warmer..as well.

Yeah, I looked up all the temperature requirements of what I would ideally like to grow, and decided to stick with those that would be hardy to zone 8; we're zone 7. That still lets me grow lemons, limes, and pomegranates, and dwarf banana trees. I use a lot of lemons in my cooking, so if I can get two Eurekas going that'll help.

yeah one zone warmer is probably a good bet but you might even get to 2 zones ..experiment..esp if you protect them with some candles on cold nights and extra protection.

I have to ask, how much sun does that area get, summer and winter?  You can also consider insulating the bottom to reduce heat loss through the concrete. 
The higher the surface to mass ratio you have the faster it will warm and cool.  One large tank will take longer to warm during the day, but will retain it's heat longer at night.
Will you have power in it?  For grow lights over starter trays and controls of heaters.

R. Peacock wrote:
I have to ask, how much sun does that area get, summer and winter?   You can also consider insulating the bottom to reduce heat loss through the concrete. 
The higher the surface to mass ratio you have the faster it will warm and cool.   One large tank will take longer to warm during the day, but will retain it's heat longer at night.
Will you have power in it?   For grow lights over starter trays and controls of heaters.

It gets light from about 9-10 am untill dusk (this is a rough estimate), so about 7 hours in winter and 12 in summer. I've been thinking of putting down a wood chip layer, about 4 inches deep, and possibly running a few chickens in their during the winter, so that it acts like a compost pile and produces heat. Another idea was to get some small quail.

I'm thinking one 100 gallon tank in the center, and then a several smaller tanks around the green house, as that's what I have. I could run power to it, but I don't know if I will yet. I'd rather do this as passively as possible, both to save money and because when the power goes out, I then won't lose everything.