Keyhole Garden
This is a great space saver idea that can work in a back yard or community garden. I think it would look nice in a front yard as well! If mine wasn't so close to a very busy street, I might have considered it since I have a rock planter out there already. I don't think the vehicle exhaust is quite going to work though.
Do you have a place to try this? Let us know how it works out!
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I wonder if a keyhole garden would hold up to Illinois winters!
I think I saw a frame for a cover over the second one they visited. Perhaps with a good cover? Seems there would need to be a heat source though. I think their climate must be just enough different from yours and mine for that to work out. :-)