Roots on the roof

by Marilena Lucci

Roberto Roselli takes ardening to the next level

“I started out not even understanding where food comes from, and now I’m so much more aware,” says Roberto Roselli of his humble beginnings into agriculture.

For the past nine years Roselli, who currently works in real estate brokerage and development, has been cultivating a not-so-secret garden atop the Caisse Desjardins du Plateau-Mont-Royal.

The rooftop garden, which started out as a hobby, is now a major summertime-source of fresh fruits and vegetables for the Resto Plateau soup kitchen across the street. “Every week I fill up bags of produce and bring it to them,” says Roselli. “We’re really focused on donating as much food as we can to the soup kitchen.”

At its highest recorded harvest in 2009, Roselli grew over a ton of produce. And he claims his rooftop growth rates are consistently higher than his backyard garden equivalents. “There’s sun all day long, a constant flow of water and fertilizer from the dripping system and animals aren’t really a problem up here. Parsley and basil are planted between the crops to deter any squirrels and birds. So, because it’s always growing, it produces more than the average garden,” he explains.

Not only does a rooftop garden produce more, adds Roselli, most of us don’t realize there are other important environmental paybacks. “Green roofs take more carbon dioxide out of the air and release oxygen at a higher altitude, which cools down the air in the city. The garden only uses 100 millilitres of water per watering. That’s 300 millilitres per day on a three-times-a-day watering schedule. A constant slow drip from the top down means you don’t need as much water. By slowing down the flow of water, everything is always humid and the plants grow more consistently.”

Regulating water accumulation isn’t just important for planting; it’s actually a huge municipal consideration as well. Dense cities like Montreal suffer from stormwater runoff. It’s what happens when rainfall excess flows over paved surfaces (instead of being absorbed into the ground), collects pollutants (oil, pesticides and bacteria) and carries them into the natural surrounding waterways. Stormwater runoff can also cause urban flooding.

Roselli explains that when it rains “each module (the garden’s water containment system) can hold over 10 litres of water, and with 135 modules —after an average rainfall—the rooftop garden retains 135 litres of water.” The rainwater accrued is saved and used as the garden’s watering supply. “My professor in urban planning at Concordia, Professor Deslauriers, really opened my eyes to what’s going on with the environment and what could be done with water and heat,” says Roselli. “He was actually the one who inspired me. He came to visit the rooftop a few years ago with his new students, which was really nice.”

Roselli hopes to share the inspiration he found on the roof with as many people as he can to raise awareness about the importance of green roofs in the city. “We need to encourage lawmakers to change polices and to give better incentives to business owners who have big rooftop spaces. Montreal is still way behind other Canadian cities when it comes to green roofs,” he says. “Of course, it requires a certain amount of discipline to maintain the garden. It’s like taking care of a pet, but the outcome is that you’re feeding yourself.”

When asked about his favourite yield from the garden, Roselli enthusiastically answers: “The celery, the mint, the tomatoes— everything! Because I know what’s in it.”