SURREY, B.C. - Business has been on fire at a Surrey, B.C., hydroponics shop since the decision was made by two U.S. states to legalize the possession of marijuana.

The ballot initiatives passed last November in Washington state and Colorado allow adults over the age of 21 to posses up to 28 grams of marijuana.

Steven Betts, a co-owner of Green Planet Wholesale Ltd., says sales have quadrupled in the last few weeks, and their multi-million-dollar businesses now employ about 60 people.

Betts says his company has plans to open a new distribution facility in Washington state in the next few months.

Simon Fraser University economics Prof. Stephen Easton says the company's success could draw the attention of competitors such as big-box stores -- especially if the owners are seeing large margins.

Green Planet's owners say it's not about doing anything illegally, and there's a sign near the store's checkout counter that warns customers they'll be asked to leave if they mention any illegal substances.