Green roofs offer an opportunity for outdoor space and gardening for people with little or no yards.
"One look out the back window was all Vivian DeZwager needed.
As her husband, Joe Maplethorpe, worked to build the garage he'd always dreamed about behind their South Tacoma, Wash., home, a solid beige wall was beginning to take shape.
DeZwager had agreed to sacrifice much of her backyard gardening space so that Maplethorpe would have a place for his woodworking hobby. But as the edifice went up, she started having withdrawal pains.
Then inspiration struck: Why not turn the garage roof into a garden?"