High Tunnel ConstructionSubmitted by josh brueggen 03 on Thu, 01/31/2013 - 11:30
I am a long time gardener, and have recently begun playing around with greenhouses and growing of hardy crops through the winter without supplemental heat. I'd like soome advice from those who feel they have some to give on the best types and varieties of plants to grow over the winter, and what I may be able to do to maximize my growing success.
My first attempt at a greenhouse was a lean to greenhouse built into the south wall of my detached garage, and glazed with insulated glass panels scavenged from old patio doors sourced off of craigslist. This structure is accessable through the garage, and can be heated via a wood stove in the garage. Last spring I used this structure to start some plants for resale. This was successful enough with minimal effort that I am planning on expanding this sideline this year. I figure I can easily make enough for my hobby to be self-sufficient, and maybe someday make a business of it.
My second attempt was a high tunnel of about 300 sq ft built over a portion of the garden. It was a simple structure of PVC hoops and plywood (OSB, whatever was in the scrap wood pile) endwalls, and it performed quite well. I don't have photos of it because honestly....it looked like garbage.
My current attempt is a larger high tunnel that has an insulated frost wall buried about 16" deep into the ground, and a 3' sidewall to improve working height. I am currently experimenting with salad greens planted in November which are still alive despite several 0 degree F nights, but are not growing in an meaningful manner. I am looking for recommendations on methods to provide some supplemental heat and light and would like to know if any fellow DP'ers have tried any methods, and what the success, and costs might be.
My current greenhouse can be seen at the following link.
And for those who are sick of winter and just want to see something green (and because I want to toot my own horn a little)
Some ideas I have come across:
Raised beds with soil heating (various methods of heating to
Double wall inflated plastic (would this be a benefit for an
Reflective covering on the north wall to maximize light levels,
and reflect radiant heat back into the structure.
Direct wood (or other fuel) heating, possibly a rocket mass heater.
Any other ideas anyone might have.
Eventually I'd like to try a double glazed highly insulated structure with heat storage via water barrels, or soil mass. I've read that they can sustain cold tolerant crops as far north as southern Canada (USDA zone 3) with passive heat only, or be used to provide solar heating to an attached structure such as your house. Has anyone had any experience with building or operating one of these?
Is anyone interested in this topic as a means to extra income or self sufficiency? Should I keep careful records of the results as I try out some of these methods? Does anyone know of any good source websites that might provide technical information on this subject? Should I continue to update my blog occasionally regarding my experiments? Does anyone care to follow along and/or compare results?