Winter Gardenagerie
05/09/12 16:39

Coleman writes a lot about temporary structures called cold-frames and high tunnels, which he distinguishes from greenhouses because unlike greenhouses, you don’t heat them at all. These structures provide shelter from freezing rain, snow, and wind, but they don’t get any more heat than they can trap from sunlight during the day. In spite of this, Coleman claims you can grow a variety of hardy leaf-crops — so that’s what we’re going to try.
There are plenty of prefab hoop houses and high tunnels to choose from. Most are made of galvanized steel, with poly sheeting. I looked at several on Farmtek’s website, but I wanted to start a little smaller. And a lot cheaper. So I started thinking about PVC.
In addition to the selection of PVC pipe sizes and connectors you can get at the Depot, there are a growing number of websites like Creative Shelters and Formufit, offering what they call “furniture grade” PVC connectors in a very wide variety of sizes and shapes. I was originally thinking about a semicircular “hoop” design, like most of the steel tunnels I’ve seen (it’s amazing how many of these things you start seeing all over, once you’re aware they exist!). But the weight of snow concerned me. And obviously, if snow is lingering on the top of the structure, light isn’t getting through.
Then I noticed that in addition to all the T-connectors, Formufit has a 45-degree angle elbow connector. And they offer all this stuff in a range of diameters, including inch and a half, which I was starting to think might be better than one inch, for a largish structure that’s meant to stand up to northern winter storms. It occurred to me that 45 plus 90 plus 45 again equalled 180, which meant I could build something that looked like a house using off the shelf parts! So in the end, I redesigned our first experimental house so it has a pitched roof.

People call this stuff tinker-toys for adults, and it’s true! Designing this and putting it together, I felt like a kid with a new Lego kit. I bought about 45 pieces of pipe for a bout $4 each. The connectors were about $270 (I bought a few more than I needed), and the poly sheeting and clip connectors to hold it on came to about $100. There’s some additional lumber for the ends (I’ll put together a detailed parts list and plans sometime soon, if it all works out as planned). So for about $600, we’ll have an experimental winter gardenagerie. That’s about a thousand bucks less than a comparably sized round cold frame from Farmtek.
So far, I’ve cut and assembled the frame, and run chicken-wire around it so the birds can start tearing up the sod. In the next couple of weeks, I’ll build the ends, put all the posts into their measured bases, and throw on the poly. And start planting the winter garden…
