Sustainable Efforts: The Garden on the Roof

In the ongoing effort to be greener and greener all the time, it might seem like enough for convention center chefs to strive to serve more organic fruits and vegetables that they buy from local farmers. Some facilities, however, want to take this aspect of sustainability to the next level. Though it isn't a common sight on the venue landscape yet, the emergence of on-site produce gardens, as well as green roofs, is creating a tiny ripple on the convention center pond – one earth-friendly facility at a time.

The David L. Lawrence Convention Center in Pittsburgh is one facility that boasts an on-site vegetable garden. On the building's fourth-floor roof terrace, also used for special events and receptions, 40 4'x10' concrete planters that once held indigenous plants now are occupied by seasonal herbs and vegetables, taking up 1,600 square feet.

According to Mark Leahy, David L. Lawrence general manager, what started a couple of years ago with chefs taking over a few planters to grow herbs expanded into a year-round vegetable garden where organic zucchini, pole beans, eggplant, tomatoes and herbs such as rosemary, thyme and basil are cultivated. Staff members of the center's food and beverage supplier, Levy Restaurants, maintain the garden and use the produce for events.

Although the planter crops don't generate enough food for large-scale catering, Leahy said, chefs often use the vegetables in dishes for small events or special tastings at the center.

“(The vegetables are) a supplement, an addition to what we're buying locally,” Leahy said.

The garden is a part of the convention center's commitment to buying fresh and supporting local growers, Leahy added.

“People are very interested in the fact that we get a lot of our produce locally … that it didn't travel 1,500 miles to get here,” he said.

In keeping with the facility's gold-level Leadership in Energy and Environmental Design (LEED) certification, requiring the facility to use plants that don't need irrigation, building management provides and maintains a special soil for the produce planters that holds and releases moisture and doesn't require extra watering. Fertilizer comes from the facility's food waste, composted at a local farm, Leahy added.

As if the addition of the garden isn't eco-friendly enough, Leahy said the facility is in the proposal stage for a 4,400 sq. ft. greenhouse that would contain a hydroponic garden with more than 9,000 plants, mostly lettuce.

According to Ron Beal, president of destination management company Absolutely Pittsburgh, the rooftop garden at the David L. Lawrence is a big hit with the groups he brings to the convention center.

“We think it's wonderful to share environmentally sound practices like that with people,” Beal said. “It's very popular.”

Down south, the Raleigh (N.C.) Convention Center also is doing some on-site growing in the form of an herb garden. According to Lyn Mayer, general manager of food and beverage supplier Centerplate, chefs grow a variety of herbs outside one of the kitchens in a terraced garden at the center that includes rosemary, thyme, dill, savory, mint, sage and aloe vera (used to treat minor burns, not to eat).

Mayer said Raleigh hasn't considered growing its own produce because there isn't much need for it.

“We have huge farmers markets just five minutes away, seven days a week,” he added, “and this helps us support our local organic growers.”

For some convention centers that practice sustainability – but may have space or logistical limitations – growing their own produce might not be an option. However, building living green roofs are a viable and eco-friendly feature with a wide range of benefits. Two Canadian convention centers enjoy – or will soon enjoy – green roofs for similar reasons, although they use them for different purposes.

The Vancouver (British Columbia) Convention & Exhibition Centre has a green roof under construction. Scheduled for completion next spring, the six-acre beachscape will have more than 400,000 indigenous plants and grasses visible, though not accessible, to the public.

According to Warren Buckley, president and CEO of PavCo, the company that operates the convention center, the green roof will act as both a buffer and an insulator for the building, with rainwater recovered and recirculated throughout the building.

“(Being green is) part of the environment in which we operate,” he added. “It's part of the world we live in and should live in. … We need to give back.”

So why not a rooftop garden? Buckley said the roof is intended to support an ecosystem without the maintenance personnel an edible garden would require. Also, the structure's limited weight-bearing capabilities prevent such a venture, he added, although a small portion of the roof may be used for the chef's purposes at some point.

On the other side of Canada, the Metro Toronto Convention Centre has a completely different use for its green roof. Expanded to two buildings in 1997, the predominantly below-ground South building is topped by a seven-acre greenscape that doubles as a public park, complete with benches and trees.

According to Vince Quattrociocchi, vice president of operations at the MTCC, the 11-year-old green roof not only has been a great addition to the cityscape, but also is an insulator for the building, maintaining warmth in winter and keeping it cool in summer.

“(The park) is another illustration of something we do to emphasize our belief in sustainability,” Quattrociocchi said.

Growing produce onsite isn't something the MTCC has looked into thus far because of space limitations, he added.

While growing produce onsite may be an easy task for some convention centers and more challenging for others, taking the locally sourced food concept to the next level is an attractive prospect.

Meanwhile, the clients and staff of the David L. Lawrence CC enjoy the appeal and benefits of their vegetable garden.

“Who doesn't like to see things grow?” Leahy said. “Although, we have caught staff eating the green beans from time to time.”