Are rooftop gardens an idea worth tending?

In the hunt for local, fresh, environmentally friendly and novel produce, the holy grail may well be the supermarket rooftop or adjacent greenhouse. What’s more local than greens grown just steps from your produce department? And just think of the supply-chain benefits: year-round product invulnerable to drought, flood, heatwaves and frost.

Only a few years ago, rooftop growing for supermarkets seemed poised to be the next big thing. Much-publicized gardens popped up in New York, London and Vancouver, promising a revolution in local. But not all of them worked out.

A 2011 initiative in the U.K., at independent grocer Thornton’s Budgens, in London, called Food From the Sky, sold fresh-picked produce grown on the store’s rooftop. It has since shut down. In Vancouver, a 6,000-sq.-ft. hydroponic, green-leaf vegetable garden and packaging facility on a city-owned parking garage supplied lettuce to a few local grocers. It lost $54 million before filing for bankruptcy protection, in 2014.

More successful has been a greenhouse perched atop a Whole Foods in Brooklyn N.Y. Started in 2011 by an urban farming outfit, called Gotham Greens, it supplies more than 200,000 pounds of leafy greens, tomatoes and herbs to nearby Whole Foods stores. Gotham has three more greenhouses (two in New York and one in Chicago), growing 20 million heads of lettuce a year.

A somewhat different local-food scheme is now in the works at a Metro Plus store in La Pocatière, Que. Store owner, Simon Lebel, recently signed on with Quebec-based startup Inno-3B to deliver “living greens” to his 100,000-sq.-ft. store, says Lebel, a third-generation store owner.

Inno-3B has built a production facility in La Pocatière for lettuce, kale, bok choy and herbs including mint, coriander and basil, which come with their own non-refrigerated, in-store display systems, water included. “It’s local, it’s fresh, there’s no refrigeration and no handling,” says Lebel.

Inno-3B’s process is unique. Produce is grown hydroponically and delivered to the store “alive,” as its president, Martin Brault, says; roots are intact, with “no pests, no fungus and no bugs.” Better still, the produce has a shelf life up to four weeks.

Brault says he’s been approached by Sobeys, Metro and Loblaw, all on the hunt for local and innovative produce. Brault’s ambitious plan, launched with an investment of close to $1 million, is to build and franchise 12 Quebec production centres by next year that would serve stores within a 160-kilometre radius. While Gotham Greens says it grows and sells 20 million heads of lettuce a year, Brault says he’s aiming for hundreds of thousands, all priced competitively with the imports.

Other indoor growing systems—such as the Farmery’s Crop Box and Freight Farms in the U.S., both of which sell systems contained in shopping containers—have, for the most part, abandoned retailers to supply hotels and restaurants. Caroline Katsiroubas, community manager of Boston-based Freight Farms, says her company has recently sold to customers in Alberta and Ontario, and some growers in New Jersey and Washington are selling to small grocers. Most, though, serve restaurants.

Metro’s Lebel, though, says his clients are keen so far on the local greens coming their way from Inno-3B. “We have talked a lot about it with our customers. They are very enthusiastic.”