I am looking into building a greenhouse on a property in the Adirondacks, in the north east of the United States. Considering that we are already heading into Fall and Winter is right around the corner, there are some concerns about what the best type of greenhouse to construct would be, and if it could be properly heated and maintained during the cold winter months. Ive done some research on greenhouses and I dont know what the best option for a smallscale greenhouse would be without having to put large energy inputs into the process in such a short period of time. It would be ideal to find a cheap and efficient way to create a productive greenhouse that could be used this winter, without exorbitant heating costs.
Does anyone have any examples of greenhouses being productive in such cold temperatures without elaborate heating systems? This is a small cabin property pretty far away from any city, so supplying the property with intense construction materials is also a problem.
passive solar greenhouses are you ticket, earth sheltered would make it even more efficient. and paul wheaton has a video of a rocket mass heater in a greenhosue as well which would make it even better. if you have wood its basically free heat if you harvest and maintain your woodlot right. but just passive solargreenhouse will be much much better than any traditional GH.
The ultimate goal of farming is not the growing of crops, but the cultivation and perfection of human beings. - Masanobu Fukuoka
posted 10 years ago
Thanks for the insight. Did some research into Walipini's , essentially a pit greenhouse. I really like the rocket stove heater, that, and a north wall lined with black drums could all together help keep the greenhouse at a good temperature. I dont know anything about growing in winter since this will be my first time living in such conditions, but I still wonder if a pit greenhouse could maintain the necessary temperature during below freezing days, the Walipini was designed for the southern hemisphere...hmmm?
Also, if anyone knows of ways to build thermal mass/cob without much clay, this would certainly be a help. I'm still brainstorming on where to place the thermal mass part of the rocket stove heater, either around the greenhouse interior perimeter or running across the middle of the greenhouse partially or fully subterranean. Seeing as I don't know the clay composition of the soil (or how to extract clay from soil just yet), I would like to have some clay-less cob alternatives available should this be an issue.
Unless you have already started the plants you intend to grow in this future greenhouse, I would say you're likely too late already for a winter harvest and should start thinking about spring. Winter crops have to get most of their growing done before the end of October, after which the days are too short without supplemental heat and light for plants to put on a lot of growth. So if you start plants in October, they will grow a bit, then sit there and wait for the Persephone months to be done, and when light gets above about 9 hours a day again, they'll resume growth. Spinach is commonly overwintered for an early spring harvest.
Consider row cover inside the greenhouse for a layer of extra protection. Grow crops that can take some frost and you have less to worry about. You just harvest them when they are not frozen. Thermal mass is your friend. Water, rock, earth, brick, etc. A properly prepared compost heap inside the greenhouse will produce a lot of heat. Partially sunken into the ground is good. Direct overhead light on the plants is key. Worry more about cooling than heating! You will understand this once you've worked in a greenhouse for a while. Top vents, and ridge vents are great, with low vents for fresh air input. Anyone's first greenhouse design will be full of mistakes. that's okay, it's how most people learn. Passive solar residential architects don't know a thing about designing a greenhouse. It is specialized knowledge.
Check out Eliott Coleman's work, such as Four Season Harvest.
posted 10 years ago
Not sure you would have time to do this, this year, but have you looked into compost heating a water line like Pex under the greenhouse. Compost reaches 140*-160* for months on end. I'm sure if you had the lines snaked under the greenhouse on a closed loop system where the water line is connected to a pump that circulates the water through the line.
I am only theorycrafting this system based on things I have read. But seems it would keep things from freezing.
Location: Burton, WA (USDA zone 8, Sunset zone 5) - old hippie heaven
posted 10 years ago
Hi Christa, the very first thing to do is to determine exactly what you intend to use your greenhouse for. Extending the season for temperate fruit and veggies is one thing, growing tropical fruit is quite another. I second the recommendation for Coleman's book. Get it from the library before you build a thing. Also, look at http://www.themodernhomestead.us/article/Greenhouse.html for an example of clear thinking about how a particular greenhouse functions in a particular homestead. Many people have thrown away a lot of money and effort building something that winds up being a tool shed.
If you build it this fall, you should certainly try for some winter crops, like hardy greens, but don't count on them for much.
Location: Alberta, Canada
posted 10 years ago
Also don't forget an attached sunroom/greenhouse as an option. It could be attached directly to your cabins south side. Earthbags do not need so much of a recipe of so much percent clay, and can be filled with what is available. And while lighting is important snow load is also a major factor. Check out angles for maximum sun from your site. Mark shadows now knowing winter shadows will be longer because of low horizon winter sun. A pit or partially underground greenhouse up against the cabin may or may not be possible depending on your site. If you go underground at least insulate the outside against the freeze zone and don't forget about drainage.
Farmers know to never drive a tractor near a honey locust tree. But a tiny ad is okay: