For Mother’s Day, Anna had 1 request: “build a cold frame for my plants before you leave town.” Well since I was leaving town on Monday, that didn’t leave much time to get the project designed, built, and installed.
A cold frame is like a small greenhouse. It is designed to be a transition area for plants. Since Anna had been growing seedlings in the basement, she needed somewhere to move them outside to get sunlight during the day, but be protected from the cold at night.
Previously, in anticipation of this project, Anna had picked up 2 skylights off freecycle. She removed all the aluminum flashing and some of the operating hardware. This reduced the weight (a little) and made it possible to operate them by hand. I already had some pallets with OSB mounted on the sides from a hay feeder design last winter. We didn’t plan to reuse that feeder again, but I had saved the panels for a future project like this. I basically built a large box to support the skylights at a slight angle. We dug out the area for the cold frame to be installed and connected all the walls together. Once the top windows were on, we loaded the bottom of the cold frame with compost that was about 6 months old. This compost still has some decomposing going on, so that provides the heat inside the box at night to prevent frost damage to the young plants. Anna put weed cloth over the compost base and then added the plants. During the day the windows are propped open, and at night they are closed.
After a little over a week in the cold frame, Anna has started to move the plants into the garden. (That is a rhubarb plant that she is standing next to, not a sapling.) Anna got her Mother’s Day wish and it only took about 3 hours to build.