The bill, which also would expand the number of drug strains available to patients from the current three to any form permitted by the Health commissioner, had been on Christie's desk for two months.
Christie vetoed the portion of the bill that would allow minors to enter the program with one doctor's referral, citing the importance of taking extra precaution since children may react to the drug differently from adults.
Currently, the program requires minors to get consent from three doctors or two who are registered with the program; adults need only one.
"Protection of our children remains my utmost concern and our regulations must make certain that children receive the care they need, while remaining well-guarded from potential harm," Christie said in the memo to the Senate.
Christie's veto comes two days after the father of a 2-year-old who is enrolled in the program approached him at a campaign event in Scotch Plains and asked him to pass the bill saying, "Please don't let my daughter die."
Brian Wilson's daughter Vivian has a rare form of epilepsy that could kill her and his family has said they're running out of time.
The type of marijuana she needs is not among the three strains available under the current law.
Vivian, like children with similar conditions, needs a strain that is high in CBD, a chemical that alleviates seizures, but low in THC, the ingredient that causes euphoria.
It takes three months to grow a new strain.
Since Christie inherited the program three years ago he has continually insisted on strict regulations, saying he wants the drug available to suffering patients but not "potheads."
In April he proposed a $1.6 million budget for the three-year-old medical marijuana program - more than twice the current spending plan - in anticipation that more dispensaries will open this year.
Only one dispensary has been authorized to open, but it has since shut down because of supply issues. A second is expected to open in the fall.
Contact Julia Terruso at 856-779-3876, @juliaterruso or firstname.lastname@example.org