|How do I build and use a cold frame in my garden for this spring?|
|Cold frames can be as simple as hoops covered with plastic, or as elaborate as a sanded wooden frame with polycarbonate glazing. The first will do for most situations, but if you want something more permanent and secure, a wooden frame is the way to go. Your extension service (ph# 703/382-5790) can provide you with plans for either type. Also, Gardener's Supply Co. (www.gardeners.com; ph# 800/863-1700) sells a high-mil plastic "fabric" glazing called PolyWeave, and it comes with instructions for different types of greenhouses and cold frames.
In your area, you can start seedling of cold tolerant plants such as spinach, lettuce and peas in the cold frame as soon as the ground can be worked. Early in the spring you can leave it shut all day, but by April, you'll need to crack
it open and/or shade it, especially on sunny days so, it doesn't overheat. I suggest that you place a min/max thermometer in the frame to be sure of just what temperature extremes you're asking plantsto stand, and adjusting conditions to moderate temps. You also can put out tomato and pepper transplants early by hardening them off in the cold frame first. Enjoy the jump on your season and the first lettuce and spinach in your neighborhood!