The first retail marijuana stores in Massachusetts could open in July 2018. But don’t count on being able to buy marijuana.

Industry experts are warning that there is likely to be a pot shortage almost immediately, since there will not be enough growers in the state to keep up with demand.

“The first places to open up will sell out in less than a week,” predicted Peter Bernard, president of the Massachusetts Grower Advocacy Council.

The way the state law is set up, recreational marijuana stores will be able to apply for licenses beginning in April, with licenses issued after June 1.

Existing medical marijuana dispensaries will have a leg up because they already have cultivation facilities in place. Someone who has to build a new facility is likely to take between 18 months and three years to begin selling marijuana due to the time it takes for permitting, architectural planning, construction and growing, said Brandon Pollock, CEO of Theory Wellness, a medical marijuana company that plans to apply for a recreational license.

“It’s highly likely in the first six to 18 or 24 months in the market there will not be enough cultivation space to support the demand,” Pollock said. Theory Wellness is planning to double its cultivation capabilities in anticipation of the higher demand. [Read more at Mass Live]