Washington state has issued its first retail marijuana licenses in a series of middle-of-the-night emails alerting bleary-eyed pot-shop proprietors that they will finally be able to open for business.

An official said the first two dozen shops were being notified so early to give them an extra few hours to get cannabis on their shelves before they are allowed to open their doors at 8am tomorrow. The move is expected to bring high prices, shortages and rationing.

At Cannabis City in Seattle, owner James Lathrop worked into the night placing no-parking signs, hoisting a grand-opening banner and hanging artwork. "I've had a long day. It really hasn't sunk in yet," he said, adding that he planned to hold off opening until noon tomorrow. He said: "Know your audience: We're talking stoners here. I'd be mean to say they need to get up at 5am to get in line."