Cheap Way to Build Cold Frames
- 1). Find a good location. If you are starting early spring planting, the best spot is one that has good drainage and lots of sunshine, preferably southern exposure. If you are extending your fall season, build your cold frame directly in your garden, surrounding the plants you want to protect.
- 2). Make or find a transparent lid. This can be an old window or a salvaged piece of clear fiberglass or Plexiglas. You can also cover a small cold frame with horticultural plastic sheeting.
- 3). Make or find material for the sides. You can use wood, hay bales, pine straw bales, old concrete blocks or bricks.
- 4). Prepare the site. (If you are protecting your fall plants, skip this step.) Remove any existing plants plus the top three or four inches of soil. Place a layer of rocks or coarse gravel inside the frame, and then add your original soil. This helps ensure proper drainage.
- 5). Build the sides of your cold frame. Place them in the site you chose. Make sure that the box matches the size of your lid; that the back wall is taller than the front wall and the back wall is to the north to allow the most sunshine in; and that the box is tall enough for the maximum height of your plants.
If you are using wood, cut the pieces to the right size to make your box, and nail them together. If you are using hay bales or a similar "block-like" material, just place them snugly together in the right shape to fit your lid. - 6). Fasten down the lid to the sides. You can use bricks, rocks, wood or anything else you find that is heavy enough to do the job, yet light enough for you to remove when you need to raise the lid. If you are using plastic try to drape it over the sides of the cold frame and then anchor it down on the ground.
- 7). Minimize air leaks. Find cracks or crevices where cold air can enter. Leaks can occur in the sides of your cold frame, but the most likely place is between the lid and the sides. Use any lightweight, fluffy material you can find such as cotton, felt, old socks or even dryer lint, and stuff the cracks with it.
- 8). If you are using the cold frame to start spring plants early, place your seedlings in the cold frame.
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