US: Rooftop farming is getting off the ground
Late this Summer, Chicago turned a green roof into its first major rooftop farm. At 20,000 square feet, it's the largest soil-based rooftop farm in the Midwest, according to the Chicago Botanic Garden, which maintains the farm through its Windy City Harvest program. "We took a space that was already a productive green roof, and we said, 'Why not take that one step further and grow vegetables on it?' " says Angie Mason, director of the Chicago Botanic Garden's urban agriculture programs. That required adding lots of soil amendment, or nutrients, to the rocky medium already up there.
The farm sits atop McCormick Place , the largest convention center in North America, and the goal is for it to supply the center's food service company, Savor Chicago, with between 8,000 to 12,000 pounds of food a year, more than 10,000 servings. It sounds like a lot, but SAVOR serves about 3 million people a year at McCormick Place.
In the first season, Mason says the Windy City Harvest farmers, which include underemployed ex-offenders, will be growing kale, collards, carrots, radishes, peppers, beans, beets, cherry tomatoes and various herbs at the McCormick Place farm. The project's coordinators chose these crops because they're well-suited to a rooftop setting and they're fast-growing.
Over the next few years, Mason says, the plan is to expand the farm to other sections of the McCormick Center roof for a total of 3 acres of cultivation. That would make it the biggest rooftop farm in the US, bigger than, which operates a farm of 2.5 acres, or 108,000 square feet, on two roofs in New York City.
Source: npr.org