I read a post on the "ThriftyFun Tips" newsletter I subscribe to about using those rooftop cargo carriers for cars for coldframes for winterproof gardening.

Well- my idea is to use an old, even rusted, barbecue gril. The "paint" should be nontoxic since we used it to cook what we eat. It already has heat trapping ability and a hinge top. Most barbecues have smoke vents on top which we could use to control the trapped heat/temperature inside. And for warmer nonfreezing weather, you could open the coldframe grill and just cover your plants with a modified/small plastic "rowcover". Plus- it's on wheels so it's easily moveable to where the sun is or isn't and it would be elevated off the freezing ground with snowcover.

The more I think of this idea (it's my original idea as far as I know)- the more I like it! We already have a spare grill that we hardly use even during the summer (only to incubate my homemade yogurt); I think winter use would be appropriate. All I have to do is check the depth allowed. I wonder if there are any more "junk" BBQs that I can pick up. LOL