Earlier this year, my wife and I redid our bathroom. As I was removing the old 1920s-era window from its frame, I really hoped that I could find a use for it instead of shipping it off to the town dump like I had with some of our other construction refuse. After looking around the net, I stumbled upon the perfect idea: a cold frame.
Old windows make great cold frames. Photo By Paul Gardener.
A cold frame is nothing but a wooden box with no bottom and a transparent roof, typically glass. These are slightly taller in the back than they are in the front, and traditionally placed facing south in order to gain the maximum amount of sun exposure each day. Cold frames allow you to get your seeds started outside earlier each year by protecting your frail seedlings from cold weather, excess water and wind. By using a cold frame, you could extend your growing season for a month or two, depending on your area. Getting your plants an early start could help you avoid the problem of too many tomatoes at once coming out of the garden at the end of the planting season.
Some of the best plants for cold frames are lettuces, parsley, spinach, radishes, turnips and other root vegetables. Once you’ve got your seeds started in your cold frame in the early spring, you can either leave them there or move them into your garden with the rest of the plants you planted that year. If you elect to remove them, make sure to fill your cold frame back up, as cold frames can still produce great quality vegetables and salad greens well into December and January!
One thing to watch out for with your cold frames is heat. If you let the temperature inside the frame get too warm (above 60 degrees), you could do damage to the plants that you’re trying to protect. If you’re going to be gone all day and are unsure about the temperature inside your cold frame, you should play it safe and vent the frame.
Cold frames are simple and inexpensive to make, and can easily extend your growing season with little work to do on your part. Once this spring rolls around, I’ll have mine ready to go and planted with yummy stuff for the dinner table.
Jeff started the website sustainablelifeblog.com in 2009 to talk about sustainability and chronicle his journey to a more sustainable life. He currently resides in Wyoming with his wife and dog.