- By adding a simple clear plastic milk jug to a cold frame you can expand your growing season by a month.
- I have several cold frames I put out in the fall and winter months for cool weather crops such as lettuce but I also use cold frames to protect perennials that I have transplanted that need another month to develop a larger root system.
- If you have a cold frame line the bottom of the frame with black plastic. One the sides you use milk jugs filled with water. These milk jugs draw heat from the sun during the day and will help keep a cold frame 5 to 7 degrees warmer at night. You can also throw a blanket over the top of the cold frame at night to help keep in more heat.
- If you don’t have a cold frame, an old window frame will work with an old window placed on top. Hay bales also make great cold frames and have extra thick walls to keep in more heat. All you need to be able to do is keep cold winds and snow away from your plants.
Just remember the milk jug. It’s amazing how much heat you will add to your cold frame with this simple jug.