The Merrimack Valley’s first recreational marijuana shop will open in Lowell this Saturday, becoming the 12th store to sell recreational marijuana in Massachusetts.

Patriot Care Corp., which operates medical dispensaries in Boston, Greenfield, and Lowell, received its “commence operations’’ notice for Lowell from the state’s Cannabis Control Commission on Monday, which gave it the ability to open for recreational sales after three calendar days.

Patriot Care also has a final license from the state to start adult-use sales at its Greenfield location.