Recycle an old swing set into a green house. Put a shelf across the middle of the swing set to add garden space, or simply hang upside down pots or planters from the existing swing set hooks. Add a climbing wire for beans. Then, set up your watering system, plant, cover with plastic and watch your garden grow. This double decker greenhouse is sure to add a couple of weeks growing time on each end of the growing season. That's a precious month for a zone 4 gardner.
Step 1: Prepare the Plot
The swing set I salvaged from a metal pile at the dump had a foot print of 5.5' x 10.5', plus we added an extra 4' of garden to one end, since I had the space.