"Although green space in cities doesn't come as naturally, the interest in variations on sustainable roofs has blossomed.
Initially, [resident Jeff] Miller said he was unaware of Washington's sizeable bee-loving community, and he aimed to place five hives throughout the district. He sold 65 last year, he said, and about 35 of them are within city lines - eight of which happily buzz on Miller's roof.
'They kinda sold themselves,' Miller said. 'In D.C. there's a keen awareness of sustainability.'"