A Quebec couple have moved to the tiny community of Saint-Léolin in northeastern New Brunswick with plans to turn a former school into a large, indoor vertical farm, capable of producing 750,000 heads of lettuce a year.

The opportunity for the farm cropped up after the village of 600 saw its school close in 2012. Saint-Léolin was dealing with a problem experienced by many rural communities: there weren't enough students to keep the school open.

Saint-Léolin Mayor Guy Cormier started looking for someone to purchase the 2,200-square-metre building after the doors closed.

About a year ago, he met Chantal Gagnon and Daniel Ratté, who were living in the United States at the time. The couple were looking to come back to Canada and for a new project to keep them busy.

They'd been inspired by a visit to a vertical farm in Florida a few months earlier.

The couple grow lettuce and other leafy greens in the room where the school's library used to be. (CBC)

"This is when we decided this is what we're going to do," said Gagnon.

"I was very excited. I grew up on a farm."

The mayor gave them a tour of the school by video chat and the rest is history.

Gagnon grew up in the Matapedia Valley of eastern Quebec, just across the border from Campbellton. And so after looking at buildings all across the country, she was drawn by the prospect of returning to a place close to home.

Vertical farming is similar to other methods of indoor farming, such as hydroponics, in that the plants are grown without soil.

Can't keep up with demand

But cultivating them in "trees" allows producers to use the space, and resources, more efficiently.

Instead of rays of sunshine, LED lights are used.

If a purple hue often radiates from these farms, it's because the lights' blue and red wavelengths provide the plants what they need.

The plants get their nutrients through a water system that constantly reuses the supply.

The couple invested $55,000 of their own money in the equipment, and right now, lettuce and other leafy greens, herbs and microgreens are being grown in the school's old library.

What was initially supposed to be just the pilot project has gotten the community so excited that Gagnon and Ratté are having a hard time keeping up with the demand.

The only sign of the couple's indoor farm right now is the purple hue coming from one of the windows, where the library was. (CBC)

"We are amazed," said Gagnon.

"We didn't think that people would respond so well."

Every Saturday morning, when they open their doors to the public, people have been lining up to buy the produce, and the crops usually sell out in a couple hours.

A Quebec couple bought a building that used to be a school in Saint-Léolin and turned it into an indoor vertical farm, capable of producing 750,000 heads of lettuce a year. 1:00

The vertical farm began selling its produce on Oct. 29 and the couple are selling at grocery store prices. Customers can pick up a head of romaine lettuce for $2.99.

Romaine troubles

Ratté is not surprised. He thinks ongoing troubles with romaine lettuce coming from California has played a big role in driving people to find alternatives produced closer to home.

He also thinks with climate change and other threats to traditional agriculture, this type of farming will only become more common.

"There's no more land anymore to grow anything," said Ratté.

"And the one we have right now, there's a lot of issues with the pesticides, with the chemicals."

Ratté said if their plants ever get sick, they are treated with vinegar and hydrogen peroxide.

Daniel Ratté thinks this type of indoor farming is part of the solution to worldwide threats to traditional agriculture. (CBC)

The couple hope to attract investors and fill every classroom with plants so they can supply customers, grocery stores and restaurants in northern New Brunswick year-round, a project estimated at $4.5 million.

Saint-Léolin's mayor said the prospect of new life being injected into the village is helping to spread the word.

"I think it's the future," said Cormier.

"I talk with other friends from other towns around, and they say you're lucky to get that in your town."