Frequently asked questions How much cannabis can I possess in Florida with an MMJ Card? In Florida, you can possess the following amounts with a valid MMJ Card: A qualified physician may recommend up to six 35-day supplies of smokable medical marijuana. A 35-day order may not exceed 2.5 ounces. Patients may only possess up to 4 ounces of medical marijuana in a form for smoking at any given time. There is a limit of 10% THC on medical marijuana products.