must be 18...a person gets there card they the can designate 2 other people and they will get a card also 1 is cargiver witch takes care of the patient and the other is the grower.... the patient can choose to be all of these themselves if they want... as a patients you can have a pound and a half dry amrijuana on you posesion at any time... when you have seperate person as a cargive and grower each person can have a half pound.. total again pound an a half.. me as a grower i can have 18 imature plant under 1foot tall and/or 1 foot wide.. and i can have 6 plants in bud.. there is no limit on size on flowering plants and no limit in wieght of wet marijuana.. that is per patient so in my case i can have 32 small plants and 12 in flower because i have 2 patients