SPOKANE, Wash. -

Colorado could be running out of marijuana and growers worry Washington could be next. Our state plans to have legal pot shops up and running by late spring, and seeing what's going on in Colorado could prove eye-opening for Washington.

The mad marijuana rush in Colorado appears to be dwindling, along with supply. Some shops are capping the amount of cannabis customers can buy to make sure they don't run out.

"I expected to have some business, but I didn't expect it to be that big," one shop owner said.

In Colorado, many of the shops are former medical marijuana dispensaries and allowed to sell the weed they already had. In Washington, that won't be allowed. Everything has to be grown after licenses are handed out in late February. 

Growers like Sean Green says our state won't have that advantage, and thinks Washington could sell out faster.

"We can add more lights, add more plants, but ultimately there's going to be a shortage," Green said.

It takes at least three months to plant, grow, and process the cannabis before it can be sold. Once growers run out, the cycle starts over.

Washington Liquor Control Board Spokesman Mikhail Carpenter says that's one reason the licenses won't all go out at once. They also haven't set a limit on the number of growers.

"The system has been designed to meet the consumption data. A lot of research went into it," Carpenter said.

Green is hoping to help the state meet its goal, and turn a profit when the rush heads to Washington. 

"So we're going to work as rapidly as possible to improve and expand infrastructure that has yet to be built, and grow as much cannabis as possible," Green said.

In Colorado, keep in mind, only 37 of 348 stores have opened. New shops are opening every day.

334 stores will be approved for the state of Washington.