We're doing that this year. Just installed (easy to do yourself) an OBC 15x48 quonset style cold frame. If it is double bagged, it can be a greenhouse. Cheap to do. Bows can be taken down or left in place. Installing and taking off again of the plastic does require two people. Double bag requires a small blower to inflate the space between the two plastic sheets. >Looking for idea's >Want to install a temp greenhouse over the top of my normal >growing area. Concept is to extend growing season spring and >fall. >Problem trying to figure out how to roll 16 ft wide plastic over the >top, tie it off, keep it secure, then remove after it gets too hot. >Any suggestions would be aprricated >Byron --