Marijuana retailers in Connecticut say a dearth of licensed growers in the state’s fledgling legal pot industry has left them with a shortage of product to sell.

The supply problem has appeared after slow retail growth in neighboring New York last year left growers there struggling with the opposite: an excess of supply.

It would seem both problems could easily be solved by shipping product a few miles over state lines. But that would violate federal drug laws. So each state that legalizes marijuana is left with its own process for licensing growers and sellers, and trying to create a balance between the two within state borders.

Benjamin Zachs, the chief operating officer of Fine Fettle, which operates five dispensaries in Connecticut, said he worries that low supply in stores is leading some customers back to their former, illegal dealers, and across state lines where he cannot go to get product.