Marijuana lovers celebrated the full legalization of the weed in Canada Wednesday as the nation embarked on a controversial experiment in drug policy attempted by only one other country.

Scores of customers braved the cold for hours outside Tweed, a pot boutique in St John's, Newfoundland that opened at midnight, to buy their first grams of legal cannabis.

Ian Power lined up outside the store four hours before its grand opening, happy to "make history" by being the first to legally buy pot in Canada. "I am elated. I am so excited; I can not stop smiling. I am not cold. It is cold out, but I am not cold," he said.

In Cape Breton, platinum record-selling fiddler Ashley MacIsaac was among the first buyers, while in Toronto revelers attended a "Wake and Bake" party with music, a glass pipe blower, and campfire treats.

In Montreal, they brought lawn chairs to lineups and burst into applause when fellow patron Sebastien Bouzats called it "an unprecedented day in the G7." "It is fun, good for the soul, and now legal so we do not have to stress about that anymore," Bouzats told AFP. "We don't have to hide it anymore."

Legalization has sent stocks in pot companies soaring on the Toronto and New York stock exchanges but has also been sharply questioned by some health professionals and opposition politicians.

Legal cannabis

It is unclear as yet if Canada's new framework of legal cannabis will succeed in undercutting the black market, as prices for illicit pot have plunged in the last year to an average of Can $6.79 per gram, and most sellers had planned to charge more

Prime Minister Justin Trudeau has defended legalization—the fulfillment of a 2015 campaign promise as intended to protect young people and to shut down drug dealers. "I do not drink coffee, I have no intention of using marijuana," Trudeau, who has admitted to smoking pot in the past, said Wednesday.

The entry into force of the Cannabis Act makes Canada only the second nation after Uruguay to legalize the drug. How well it goes could have an impact on Canada's next election in 2019, and on whether other countries follow in its footsteps.

A new industry is born 

Under the new regulations, Canadians at least 18 or 19 years old (soon to be 21 in Quebec) will be allowed to buy up to 30 grams of cannabis, and grow up to four plants at home.

A patchwork of private and public cannabis retail stores and online sales have been set up across the 13 provinces and territories, ramping up to 300 storefronts by year's end, the government predicts.