How to Build a Cold Frame

How to Build a Cold Frame

Are you looking to get a jump on your spring lettuce crop? Having trouble getting your eggplants seeds to sprout on the window sill? Perhaps your spouse doesn’t appreciate soil, seeds and peat containers all over the house for 2 months during late winter? Sounds as if you need a mini greenhouse or cold frame to solve your problems. Here are easy directions for how to build your own.

Step One: Stop and pick up old windows from the curb- the bigger the better. Plenty of people throw away old windows when they get new ones. If you’re shy about other people’s trash, try calling a window contractor and asking what he does with the old windows he replaces. Offer to trade him vegetables for them.

Step Two: Measure the glass from frame to frame

Step Three: Cut scrap wood at least 6″ wide to match your measurements. Leave an inch or so for wiggle room.

Step Four: Hammer together your frame and set the window over it.Step Five: Set it in a sunny location and you’re ready to go. In no time you’ve created a warm spot to start your veggies.

Additional Hints: Remember to leave your cold frame open slightly on warm, spring days so as not to cook your seedlings. You can add a hinge to make it easier to get into your cold frame. You can also build or site your cold frame in such a way as to angle it to receive sunlight more directly. Happy farming!

[UPDATE] Here is a drawing that might aid some of your attempting this at home. Please click on the image to blow it up, or you can directly download the PDF file here.