When Canopy Growth opened its first cannabis factory in an old chocolate plant near Ottawa four years ago, it did so predicting a bright future. Canada had already legalized medical marijuana, and Canopy predicted full legalization for recreational use to be next.

What the company hadn't predicted, however, was the sudden flood of foreign visitors. Politicians and police authorities from Jamaica, Germany, Denmark, the Netherlands, Greece and Australia have all come knocking, as well as doctors from New Zealand, Brazil and Chile, along with groups of corporate investors and bankers – so many that Canopy now sometimes splits up the groups according to their birthdays.

"We knew we'd have to give a lot of tours, so we just cut a window into the wall," said the company spokesman, Jordan Sinclair. "We put windows in all of the doors."