Canada’s First Legal Weed Was Grown in a Mine: The Forgotten Story of Prairie Plant Systems

How Canada’s First Legal Cannabis Was Grown Underground

In the year 2000, while dot-coms crashed and political power shifted in the U.S., something much quieter — but far more historic — was happening in Canada. A small biotech firm from Saskatoon, Prairie Plant Systems, inked a deal with the federal government to produce the country’s first legal cannabis.

But this wasn’t your typical indoor grow. This weed was grown 500 feet underground in a decommissioned zinc and copper mine in Flin Flon, Manitoba — a place better known for mining hockey prospects than cultivating high-THC buds.

This is the strange and mostly forgotten beginning of Canadian legal cannabis, and the underground roots of what would later become a billion-dollar industry.

The Legalization Origin Story: From Courtroom to Cultivation

The late '90s were a turning point for medical cannabis in Canada. In 1997, a man named Terry Parker, living with epilepsy, won a landmark constitutional challenge (R v. Parker), forcing the government to provide access to medical marijuana or risk violating the Charter of Rights and Freedoms.

Scrambling for a solution, Health Canada created the Marihuana Medical Access Regulations (MMAR) and decided on a single-source cannabis supplier. That supplier would be Prairie Plant Systems — a company better known for controlled plant growth in biotech applications than anything to do with weed.

This contract, worth $5.75 million over five years, made Prairie Plant Systems the first licensed cannabis producer in Canadian history.

Why a Zinc Mine? The Flin Flon Grow Operation Explained

When Prairie Plant Systems proposed growing cannabis in a former mine shaft owned by Hudbay Minerals, it sounded bizarre — but it worked.

The Flin Flon mine offered:

• A controlled environment with consistent temperatures

• High security, with limited entry points

• Isolation from public view or potential theft

Inside the mine, PPS built a fully sealed hydroponic cannabis facility, complete with artificial lighting, climate control, air filtration, and round-the-clock monitoring. This was Canada's first legal indoor cannabis grow, and it was deep underground.

The Quality of Canada's First Legal Weed: Government-Issued Schwag?

Between 2001 and 2013, thousands of Canadian patients received weed from this underground facility via Health Canada’s medical cannabis program. Packaged in government-stamped foil pouches, the cannabis was gamma-irradiated to kill microbes and shipped to patients who had no other legal source.

The reviews? Not great.

Patients often described it as:

• Dry and dusty

• Low potency

• Harsh-tasting

• Lacking in strain variety

Despite the criticism, PPS held the contract for over a decade — the only legal cannabis supplier in Canada, effectively a monopoly.

From Prairie Plant Systems to CanniMed: Going Public and Getting Bought Out

In 2013, as Canada transitioned from MMAR to the new Marihuana for Medical Purposes Regulations (MMPR), Prairie Plant Systems created a subsidiary: CanniMed. It became one of the first licensed producers under MMPR, swapping the mine for a high-tech indoor grow in Saskatoon.

CanniMed quickly scaled, becoming a recognizable name in the early Canadian medical cannabis market. In 2016, it went public on the Toronto Stock Exchange, part of the first wave of cannabis stocks drawing serious investor attention.

Then, in 2018 — during the peak of pre-legalization hype — Aurora Cannabis launched a hostile takeover and acquired CanniMed for $1.1 billion, making it one of Canada’s first major cannabis M&A deals.

The Legacy of Prairie Plant Systems in Canadian Cannabis History

The story of Prairie Plant Systems and the Flin Flon mine is often overlooked in the narrative of cannabis legalization in Canada, but its impact was massive.

• It laid the foundation for legal cannabis production in Canada

• It pioneered secure, indoor cannabis cultivation under federal oversight

• It set the precedent for federally licensed cannabis producers (LPs)

• It helped push medical cannabis from legal grey area to government program

Most importantly, it proved that cannabis could be regulated, standardized, and scaled — even if the product wasn’t perfect.

From Mine Shafts to Dispensaries: How Far Legal Weed Has Come

Today, Ontario alone has over 1,700 licensed cannabis retailers, and Canadians enjoy access to thousands of legal cannabis products, from craft flower to THC beverages. But it all started with a single grow, underground, in one of the most unconventional environments imaginable.

While craft growers and BC Bud legends get their fair share of the spotlight, the story of Canada’s first legal joint starts not in a greenhouse or dispensary, but in a zinc mine in Manitoba, grown under fluorescents and sealed in government packaging.

In a country now flooded with cannabis brands, that origin story still stands as one of the most surreal chapters in the Canadian cannabis industry.