SECAUCUS, N.J. — Tucked inside a nondescript commercial warehouse here sits a sophisticated marijuana-growing operation. A custom filtration system feeds a proprietary cocktail of nutrients into a hydroponic, two-level farming system. Two pallets of crops are harvested every day, and the 15,000 square feet will eventually yield two tons of marijuana per year.

And it’s all legal.

Opened just a few weeks ago, Harmony Dispensary is the latest site in New Jersey to provide marijuana for medical use, a program that has expanded greatly since Gov. Philip D. Murphy, a Democrat, was sworn in. More than 10,000 patients have enrolled since he took office in January, bringing the total to about 25,000. And on Monday, Mr. Murphy’s office announced it was seeking up to six new applicants for medicinal marijuana dispensaries.

“There’s been a very steady flow of patients since, literally, an hour after we announced the opening,” said Shaya Brodchandel, the chief executive of Harmony.

But business could be even better.

Mr. Murphy campaigned heavily on a promise to legalize marijuana for recreational use, which would make New Jersey the 10th state to do so, and the first in the New York City region. Full recreational legalization was projected to generate $80 million in annual tax revenue, according to Mr. Murphy’s budget proposal.