Hi. I'm thinking you mean gardenia. I've never heard of garenia, and can't find it in any reference material. So, if you've got gardenia, falling buds and yellowing leaves would most likely indicate too little water. But black branches would most likely indicate fungus and death, and since you listed that first, probably not the case. I, too, live on the West Coast of Fla, I would put a gardenia in the ground, but if you want to keep it potted, why don't you try first a bigger pot, fresh soil, and more water. Let it settle in, wait till you see some new growth, then fertilize. Do some research on gardenia, see what you come up with. Good luck.