Cold frame gardening is an inexpensive way to extend your growing season into those winter months. You can build your own cold frames, or purchase ready-made or easy to assemble cold frames from a garden supply store.
 
Before you dive into cold frame gardening, you should know a few basics that seasoned cold frame gardeners have learned.
 
A: Area- Where to Put Your Cold Frame

Cold frames can either be placed on top of the ground, or below ground level to help take advantage of the insulating properties of the earth. Your frame should be placed in a manner to take maximum advantage of the sun. Position your cold frame at a ten-degree angle, facing in a southerly position. You can also select an area with a slightly sloping landscape to assist with drainage inside the cold frame.

B: Befitting-What to Grow in Your Cold Frame

Some plants thrive inside a cold frame environment. Gardeners most often place leaf lettuce, spinach, chard, carrots, and even evergreen starters in a cold frame. Depending on your climate and the quality of your cold frame, you can experiment with other hardy vegetables and houseplants to see what you can grow in your area.
 
C: Climate-Temperature Control in a Cold Frame

Since cold frames essentially act as miniature greenhouses, monitoring and adjusting the internal temperature of the frame is necessary to ensure the survival of your plants. Even when the air temperature is cooler in spring or fall, direct sunlight may heat the air inside your frame to a temperature that will fry or wilt your plants. Opening the sash of the cold frame is often sufficient to vent trapped heated air and protect your plants. A simple window-mounted thermometer is often all that is required to help you monitor your frame’s temperature.
 
When the temperature drops below 20 degrees, your cold frame will need some additional insulation to keep your plants from freezing. The easiest way to add some winter insulation on those bone-chilling days is to use burlap, newspaper, or old blankets to help insulate the frame. (Be sure to check back and remove the insulation once the temperature warms up.)

Gardening in a cold frame is a fun and easy way to experiment with this late producing plants, and extend your gardening hobby into the winter months. Placement, climate control, and plant selection are the three key points to remember when embarking on your cold frame gardening adventure.
 
You can build your own cold frame by visiting Garden Gate Magazine: http://www.gardengatemagazine.com/main/pdf/coldfram.pdf.