New Jersey's first state-sanctioned medical marijuana dispensary can open whenever it's ready, the state Health Department announced Monday, meaning legal pot is on the verge of becoming reality for some patients after years of political battles and bureaucratic delays.

Greenleaf Compassion Center in Montclair has cleared all its regulatory hurdles and was granted a license to become the state's first dispensary, Health Commissioner Mary O'Dowd announced Monday.

Most states don't allow medical cannabis, which remains illegal under federal law. But among the 17 states that have adopted laws to allow it, New Jersey's is both the strictest and has taken the longest to get rolling.

The New Jersey law was signed in January 2010. But there were holdups as the state drafted regulations for exactly how it would work, then more delays as five of the six nonprofit groups chosen to participate in the program struggled to find towns willing to accept them.

Greenleaf was the exception. Montclair officials allowed the dispensary in a downtown storefront. The group has been growing pot elsewhere at a site that it will not disclose.

The group received permission in April to start growing its first crop, and had planned to start selling to patients in September. But the opening was delayed because the town government did not issue a certificate of occupancy over a problem with an air conditioner. That has since been resolved.

O'Dowd said Monday that she did not expect Greenleaf to open immediately, but that the final approval means it can begin making appointments with patients.

Joseph Stevens, the president of Greenleaf, did not immediately return a call after the license was granted. But he said earlier in the day that there was no clear timeline for opening.

O'Dowd said the department is asking Greenleaf to call its patients in the order they were registered.

She said that so far 320 have begun registering to be able to use medical marijuana and 175 physicians have signed up to recommend it.

O'Dowd said that now that Greenleaf has been licensed, registered patients who selected it as their dispensary will start receiving their cards in the mail this week.

Under the state's law, patients with only a handful of conditions, including multiple sclerosis, glaucoma and terminal cancer, are allowed to access the drug. When they do, the potency will be regulated by the state.

Advocates for medical marijuana say the drug helps relieve pain and nausea.

Of the five other groups allowed to start work on dispensaries, three are still looking for homes. One in Egg Harbor Township has approval, and another has selected a location in Woodbridge.