skyline vegetable convention

Overlooking the Windy City’s articulated skyline a handful of urban farmers has climbed up to the convention center‘s roof to cultivate 1/4 acre of prime real estate. McCormick Place West, as its known by locals, was built in 2007 with three acres of extensive green roof overhead. The convention center’s catering company, Savor Chicago, decided to take advantage of this local acreage by partnering with Windy City Harvest – the Chicago Botanic Garden’s urban agriculture program that provides hands-on training – to convert a portion of the green roof into the Midwest’s largest rooftop farm. Everything grown on the roof travels downstairs to fuel the convention center’s 3 million annual visitors with local, roof-fresh fare.

Rooftop farmer Audra Lewicki and Windy City Harvest manager Kelly Larsen showed me and my mom (who was in town for the Midwest Roof-to-Table Launch Event) around their farm last week. The 1/4 acre is divided by paver walkways into five beds, each containing four test plots where varying levels of soil amendments are added. Converting the building’s green roof into a row farm involved transplanting existing Sedum to non-productive areas of the roof, removing renegade Allium, and planting crop rows along the existing surface drip irrigation system. As a result, Audra and company planted various crops systematically with 0%, 30%, 50%, and 70% amendments (by volume) in the hole of each veggie start. The growers collect observational data daily.

What can possibly be grown in 4″-6″ of granular green roof media, you ask? Windy City Harvest grows kale, tomatoes, peppers, basil, head lettuces, bush beans, chard, dill, cilantro, parsley, and yes, even root crops: onions, carrots, beets, and radishes. Who knew?

The growers plan on doubling the size of their operation by cultivating garlic and onions on a lower roof area, which will bring the production space up to 1/2 acre (approximately 22,000 square feet). An additional 2,000 square feet of ornamental planters in an adjacent patio seating area now also contains edibles, thanks to Windy City Harvest’s ingenuity. Kale, peppers, pole beans, edible flowers, and herbs artfully paint the understory of ornamental trees within the planters, providing rooftop visitors and passersby within the building with some serious food for thought.

“People love it” Audra explains, with a twinkle in her eye. “Visitors often make their way up here… The [building’s] landscaper says, ‘It makes my heart feel clean’.”