Bernheim Arboretum and Research Forest is conducting experiments to determine which grasses, flowers and herbs work best when planted on rooftops. The Courier-Journal reports that the experiment called "Gardens in the Sky" involves three garden beds and two bee hives on the roof of the American Life Building in downtown Louisville.
The gardens are planted with mostly native species of grasses, flowers and herbs. The bees aid in pollinating the gardens.
Bernheim also is observing gardens on the roof of the Metro Archives building, which does not have beehives.
"We're looking for drought-resistant, low-maintenance, beneficial for wildlife, aesthetically beautiful plants that can live basically without human interaction on green roofs," said arboretum nursery manager Renee Hutchison.
Rooftop plants at the American Life Building include purple prairie clover, dianthus and rattlesnake master. It is the third season for the garden beds, but the first for beehives.
"It definitely helps with blooms and seed set for plants, which helps with our studies of which plants recruit, which plants don't, and the evaluation of how plants grow on green roofs," Hutchison said.
On a recent day, Lani Basberg and her husband Jens, tended the hives, which are kept in place with cinder blocks and bungee cords so that strong winds don't blow them away.
Basberg says they have collected 200 pounds of honey from the rooftop hives this season _ which is unusually large.
"The honey that bees make depends upon what they forage on," Basberg explained. "Clover honey is a light color." However, the honey she gets from the rooftop hives is dark. "I don't know what they got, being a city bee, but they got something really dark all summer long."
The rooftop hives are the Basbergs' first foray into urban beekeeping, though they have 40 hives in rural Shelby County. Lani Basberg says she is a little self-conscious while on the roof in her white beekeeping suit and netted hat.
"When I'm out here, I feel like I'm just waving to all the people in the bank buildings, because you know that they're all sitting in the window, wondering what we're doing out here on the roof," Basberg said.