An hour's drive south of Canada's capital, past snow-covered pine forests and farmland, Chuck Rifici is growing marijuana at an old Hershey's factory.
He plans to sell it for medical use under a new government scheme starting on April 1 that will ban home cultivation in favour of large commercial greenhouses.
Rifici's start-up Tweed Inc is one of only six companies so far to earn a growing licence from Health Canada, and will be the first in the world to be publicly traded on a stock exchange.
Security is airtight - as required by the new federal regulations. Staff must swipe ID cards each time they enter and leave a room, and the facility in Smiths Falls is under constant video surveillance.
"It's like manufacturing inside a bank," Rifici said during a tour of the facility. "But otherwise, it's just like any other horticultural operation."
Inside, workers wearing lab coats and hair nets are constantly pruning the plants. Heat, humidity, carbon dioxide, air flow, nutrients feeding and light (12 hours on, 12 hours off) are monitored and controlled by sophisticated software.
Hershey's used to make chocolate here, but the factory closed six years ago, after five decades in operation.
Tweed, with almost Can$10 million ($A9.99 million) in "seed money", has moved in and plans to distribute its marijuana across Canada for medical use.
When renovations are completed, the Tweed factory will contain 30 growing rooms containing 1,300 plants each, as well as a "mother room" for seedlings.
"It'll be bright like the sun in here," said Rifici, pointing to bulbs being installed in one room. Workers will need to wear sunglasses, long-sleeved shirts and sunblock to enter, he said.
The marijuana itself, once cut and dried and packaged, will be stored in a secure vault awaiting shipment by mail or courier to customers.
The use of marijuana for medicinal purposes was effectively legalised in Canada in 1999.
Government figures show more than 37,350 Canadians have prescriptions for medical marijuana. The typical user is male, in his 40s, and smokes 10 grams per day.
Health Canada originally tried supplying the drug, growing it in an abandoned mine shaft in the far north, but it was widely panned as weak.
Thereafter nearly 30,000 home-based growing operations were allowed to crop up. But local officials complained about a lack of monitoring, and police worried about an increase in crime.
Under the new regulatory regime, all these small gardens will be replaced by fewer but larger commercial operations.
