Has anyone every made any cheap green houses as opposed to buying store bought expensive ones? If so, I'd like to hear about it I have a store bought greenhouse. Instead of having shelves in it i just plant my garden on the ground. No problem with the plants getting root-bound and they grow taller and I like the 'jungle' feel of it. But when I want to 'incubate' my plants and herbs before the season is ready and my greenhouse is full, I make a makeshift greenhouse out of hay bales and a used window that I can get at any salvage yard. To keep some airflow inside the greenhouse I use a concrete tile that's thin and I place then in between two hay bales on two sides of the set up. I plant my plants in a raised bed and I get eight 2ftx4ft hay bales and put 2 hay bales on top of one another on each side of the raised bed to create a cube around the plants. I then use the window to put on top of the hay bales to keep it insulated. This year I am thinking of experimenting with the above plus plastering the outside with mud to keep it more insulated. What do you guys think?