Mile Higher chocolate bars made at Incredibles kitchen in Denver ready to be packaged. 

(Photo: CPR/Ben Markus)
Colorado's recreational pot sales jumped nearly 30 percent in March, according to sales tax reports issued by the state on Thursday.

The state Department of Revenue says that Colorado sold nearly $19 million worth of recreational pot in March, up from about $14 million worth in February.

But even though all this money is passing between pot consumers and retailers, marijuana business owners still have to run their enterprises only in cash.  Banks can’t legally do business with pot stores since marijuana is illegal under federal law, and banks are governed by federal law.

In the final hours of this year’s legislative session, Colorado lawmakers signed off on a bill Wednesday that's intended to help provide banking services for marijuana retailers.

The bill attempts to set up a financial co-op that would give the industry some banking services.

But Jenifer Waller, Senior Vice President with the Colorado Bankers Association, says the bill won’t do a thing to solve the problem.

The Associated Press contributed to this report.