With the imminent legalization of marijuana for recreational use and increasing demand for medicinal cannabis, commercial grower Tweed is more than doubling its production space in Smiths Falls — and its sister company Tweed Farms was approved Thursday to sell product through its Niagra-On-The-Lake location.

Bruce Linton, chief executive of Canopy Growth Corporation, a $260-million publicly traded company with Tweed, Tweed Farms Inc. and Bedrocan under its umbrella, called the company’s newly-acquired licence a “major milestone” that gives it the green light to produce medical marijuana in what might be — at 350,000 square feet — Canada’s largest greenhouse.

All three brands are licensed suppliers under Health Canada’s Marihuana for Medical Purposes Regulations (MMPR) program, which provides Canadians with pharmaceutical grade cannabis to treat people with chronic and terminal illnesses.

“We acquired the greenhouse 22 months ago to position ourselves as a large scale, low-cost producer capable of supplying a sizable...