Back in 2014, we looked at Tweed Marijuana Inc. (now called Canopy Growth). Read what we had to say about the company in its first year.

The growing trend toward marijuana legalization has spurred a great deal of investor interest, including a recent question from a member of our Inner Circle. However, we have yet to come across marijuana investments we are prepared to recommend as buys.

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Tweed Marijuana Inc. (symbol TWD on Toronto; www.tweed.com) began trading on Toronto on April 3, 2014.

The company is a licensed grower of medical marijuana in Canada. It produces marijuana at a facility in Smiths Falls, Ontario, and through Park Lane Farms in Niagara-on-the-Lake, Ontario.

The company shipped its first product on May 5, 2014, from the Smiths Falls plant.

On May 14, 2014, Tweed sold 4.7 million shares at $3.20 each to raise $15 million.

The company bought Park Lane Farms on June 19, 2014, for $2 million in cash and shares. Health Canada recently approved this facility as a licensed producer of medical marijuana, and Tweed has started production in its 350,000-square-foot greenhouse.

Tweed sells into a limited and highly regulated market. New competitors—including Bedrocan Cannabis (symbol BED on Toronto) and OrganiGram Holdings (symbol OGI on Toronto)—continue to emerge.

Investment advice: A larger, more profitable marijuana market could set back small growers

Moncton, New Brunswick-based OrganiGram aims to sell to the Eastern Canadian and French-speaking markets, while Toronto-based Bedrocan has a licensing partnership with Dutch medical marijuana producer Bedrocan BV, which supplies the Canadian firm’s product.

Mettrum Ltd. and PharmaCan Capital, a holding company involved with three licensed producers, are two other marijuana firms that are expected to sell shares to the public and begin trading in the coming weeks.

Medical marijuana producers have a lot of speculative appeal. Many investors see legal marijuana production as a wide open field with low barriers to entry, other than satisfying the regulatory requirements. This, though, is no guarantee of profit.

Small marijuana producers have to overcome all the usual obstacles that small and start-up companies face. But if the legal marijuana market grows large and profitable enough, major agricultural and drug companies are likely enter the field and take sales away from small growers like Tweed.

We don’t recommend Tweed Marijuana or any other marijuana stocks for that matter. If you own any of these stocks, we think you should sell.

This article was originally published in 2014 and is regularly updated.