Upcycle an old window into a DIY cold frame with this Raised Bed Revolution excerpt, which provides step-by-step directions, photos and a project plan.
Garden Accessories & Outdoor: 5 tips to successful cold frame gardening
Coldframe I could make with some old windows!
How to Build a Removable Cold Frame on top of your raised veg beds. (via Three Dogs in a Garden)
15 Cheap & Easy DIY Cold Frame Ideas for Year-Round Gardening Idea: build walkways between raised beds wide enough to accommodate straw bales. That way I can plant directly into the garden beds and avoid transplanting shock in seedlings.
Cold frames offer a simple way to protect plants from frost, but take care to vent these season extension devices to avoid overheating your plants on sunny days.
installing pavers around the the cold frame area as a stable foundation