A massive piece of farmland in Langley, B.C., has been converted from a produce greenhouse into Canada's largest licensed cannabis facility.

The country's largest pot producer, Canopy Growth, has turned a bell-pepper farm in Aldergrove into a cannabis operation that will span 275,000 square meters, once construction is complete. That's equivalent to nearly 176 NHL-sized hockey rinks.

The company claims the site is now the biggest licensed facility in the world after receiving the go-ahead from Health Canada two weeks ago.

"It's a bit of a relief that we can get this in the ground," said Andrew MacCorquodale, general manager of the company's western operations.

"I think everyone viewed the receipt of the license as, 'we've made it to the starting line and we've got to get growing.'"

MacCorquodale says the reputation of B.C. bud made the province an attractive option for the Ontario-based company, which owns about a dozen other facilities across the country.

"B.C. has always been known to create great cannabis, globally," he said.

"It was very important for us to ensure that not only did we have a large footprint ... but we also brought in some of that cultivation expertise that exists in B.C. that has made it so popular among consumers."

These cannabis plants are only five or six days old. In about 2½ months they will be harvested and turned into dried cannabis flowers, gel capsules or oils for medical marijuana use. (Lien Yeung/CBC)

From produce to pot

The greenhouses sit on Agricultural Land Reserve land.

With farmers facing shrinking profits, cannabis has become an attractive alternative to produce especially ahead of the expected legalization of the drug later this year.

Last June, a farmer in Delta said making the switch to pot was likely going to bring in 15 times the company's vegetable-based revenue.

Township of Langley Mayor Jack Froese says he isn't overly concerned about the conversion, as he sees cannabis as being similar to crops like tobacco or hops for beer.

Some residents have expressed their concern to him about the potential threat to food production, but he points out the issue is outside of municipal control.

"It's been ruled by the Agricultural Land Commission and also by the federal government and their regulations trump municipal regulations."

Because of the heavy security needed to protect the valuable crop, he says he'd prefer to see the facilities operate in industrial areas.

These long rows of glass greenhouses in Aldergrove hold hundreds of thousands of pot plants. Cameras and laser sensors dot the outside of the buildings to prevent intruders. (Lien Yeung/CBC)

It's a request he says was made by several agriculture-based municipalities to the province back in 2013, but they were denied.

An independent review of the province's ALR policy is underway and the growth of cannabis is included as part of it.

Froese is doubtful though, that companies like Canopy Growth would be uprooted as a result of the process.

"They've spent millions of dollars. I find it very hard to believe that the government would now come along and say to them they can no longer operate," he said.

Results from the review are expected at the end of this year or early 2019.