|Photo from here.|
- You can build the body of the frame with wood, straw bales, cinder blocks, or bricks.
- You can build the cover/top of the frame with materials like twinwall polycarbonate, glass windows, plastic, doors...
- The cold frame works best if the cover is sitting at an angle. So, the back of the cold frame should usually be 3 to 6 inches taller than the front. This allows maximum sunlight to enter the structure and also ensures rain or snow don't collect on top.
- Try to face the frame south.
- Try to insulate the frame as best you can. Make it underground instead of raised, or build some soil up around it, or use straw bales. Also, fill in holes. If you're making the frame with brick and if the cover is slanted, you'll need to fill in some holes at the top of the frame (where the bricks are stacked unevenly to make the angle).
- Avoid building a frame at the bottom of a slope, which could be a frost pocket.
- Build the frame in the sunniest spot in your yard.
- Mary Mary
P.S. The tips came from... you guessed it, the Year-Round Vegetable Gardener.