In my state you can grow 12 for yourself. If you are a caregiver you can grow 12 for each patient you have. You can have 6 patients, one of which is yourself, so you can grow up to 72 plant at one time.
Oh, and you're only allowed to possess 2 oz of dry ready to smoke weed. I think they really need to rewrite that law Because I never have more than 4 plants, and I'm not gonna admit to being a lawbreaker or anything, but.....let's say 2oz is an extremely unreasonable amount given the number of plants you can have. And if you're maxed out on patients as a caregiver, I believe you can have 15 oz total. Again, ridiculous for that many plants.