http://www.motherearthnews.com/Organic-Gardening/Low-Tunnels-Quick-Hoops.aspx If any of you haven't ready Eliot Coleman's books about winter gardening and the year round harvests he gets, then it's highly recommended reading. Even if you have nothing in the ground yet, buy the book and make plans for an early spring garden of cool weather favourites. You can have a harvest of things like peas and broccoli weeks sooner than without protection.
Another thing you can do is to have a greenhouse. Now many of us aren't lucky enough to have a permanent one so we make do with our poly tunnels. I love mine. I've had them stand through snowfalls, wind, hail, you name it. And if you search this blog you'll find more info about building them but basically they consist of 2- 10 foot lengths of plastic water pipe slipped together and then bent into a 'c'shape and the ends either pushed into the soil or anchored by sliding them over a piece of rebar that's in the ground or on a frame. Once you have them set up you move onto another set of poles, making hoops until the greenhouse is as long as you want. You can run a ridge pole to keep the spacing even and then put over your plastic or shade cloth, whatever you're using. Our poly tunnels are basically 8-12 feet wide depending on how tall you make them and as long as we need. You can extend as far as you like simply by adding more hoops. The ends can be enclosed in any way that takes your fancy or by just grabbing the plastic and tying it out to a stake in front, like the illustration above but on a larger scale. I like to have an end that's flat so I can make a doorway. When it's very hot you can just have a chicken wire wall on the end to provide good ventilation and prevent overheating while still keeping out your chickens and goats and other pesky critters. One thing...give yourself plenty of room to walk in your greenhouse and you'll find that the ventilation is better simply by virtue of having room for the air to circulate.
Here's a great greenhouse. I'd love to build one...and it's made entirely of lego. Made for the London Design Festival, this example of Lego Architecture is getting lots of attention for it's creativity and usefulness too. It's going to be on display until the end of the week in Covent Garden and is made of approximately 100,000 Lego bricks. Even the soil inside is made of brown lego. Not sure how that' going to work for plant nutrition in the long run but certainly eye catching for the present. Right now it has flowers in it and some lettuce. Not what I'd grow, but hey. Think of what a great winter project it would be to build one of these! Bring on the Lego!