Temporary carports lining a Montreal street are full of what you might least expect

A collection of temporary carports have cropped up on a Montreal street this winter, draped in transparent, polycarbonate sheeting rather than white plastic tarps that flap on windy days.

But these tempos aren't for vehicles.

"On this street, before our greenhouses, it was just parking spots and now it's vegetables that grow," said Héloise Koltuk.

She's with Laboratoire sur l'agriculture urbaine, a Montreal-based organization that is focused on urban agriculture research and innovation. It has teamed up with a food advocacy group, the Carrefour solidaire centre communautaire d'alimentation, and this is the second year the two non-profit organizations have worked together on this greenhouse initiative.

The modified tempos are not heated. They are passive solar greenhouses that are carefully designed and managed to absorb heat during the day and slowly radiate that heat when temperatures outdoors drop.

Last winter was more of a trial run, and adjustments were made. This winter, despite the rollercoaster temperatures that have spiked and plummeted to well below zero, green is bursting from planters.

"We picked plants that are easy to maintain in cold temperatures," said Émilie Klein, with Carrefour.

There are different varieties of lettuce and cabbages along with bok choy, radishes and other root vegetables. There's also swiss chard, mustard, kale and collard greens.

Growing food in specialized containers

The tempos are tucked between a bike path and skating rink just east of downtown. Inside, hundreds of vegetables grow in 39 pots that can be covered and insulated when necessary.

"Most plants only need about 12 inches of active soil for their roots to grow in," said Beccah Frasier, as she gave CBC News a tour.

"These are smart pots. There's a fabric that you can grow most vegetables in, no problem, and they work really well on the pavement."

WATCH | Take a tour of Montreal's street greenhouses: 

Frasier, with Carrefour, said the tempos are being used because it would have been more complicated to get permits for a traditional greenhouse structure.

It was balmy inside the tempos on Tuesday, with the soil temperature around 10 degrees. It gets quite warm on sunny days because of the greenhouse effect, Frasier said.

"The greenhouse is so humid that we don't need to water from December until April," said Klein.

Supported by borough

The project is located on Dufresne Street, between Larivière and Rouen streets. An array of edible plants are grown outside there in the summer as the stretch of pavement has been dubbed the Promenade des saveurs, French for Flavour Way. Passersby harvest some three-quarters of the food grown there.

With the tempos set up in an initiative supported by the Ville-Marie borough, the plants growing inside concentrate their sugars and proteins in their cells to reduce their freezing temperature.

This in turn makes for delicious eating — a tad sweeter than you might find in a summer garden.

Not only are the three tempo greenhouses growing food for the community, but the project serves as a demonstration of what is possible within city limits, even in the winter.

"In a lot of boroughs, you're not allowed to have a greenhouse on private property, but you can have a tempo to protect your car," said Frasier.

Using a tempo to grow food is a cheeky way of calling to question municipal policies that allow people to protect their cars with plastic tents, but restrict them from growing food at home, she said.

Montreal's urban agriculture strategy launched in 2021 underlines the need for boroughs to relax regulations in order to allow new and different types of food-growing projects, including greenhouses.

Carrefour runs a pay-what-you-can collective kitchen and works with a nearby elementary school, allowing kids to plant, grow and eat greens.

Organization heads now hope more community groups will take note of the tempo greenhouse project and start planting in the winter too.

"You're never going to get your entire food needs met from a garden and particularly a public garden," said Frasier, but at the same time, residents have been showing support for the street-based, food-growing initiatives.

"So there's definitely an aspect of food security to it that I think is important."