Your right that most of our native stuff is probably considered tropical, but like Hap, I tend to push the envelope. For the most part we can get away with it, but this has been an unusual winter, I hope it doesn't bode for an unusual summer, meaning stronger hurricanes. Also, I suppose even in the tropics or sub-tropics, different things do better in some areas then others. Most of my perennials I put in for a butter fly garden were tropical and all survived, not only survived but doing well, while my Desert Rose (potted) couldn't make it. But even with those, the ones I had planted in the ground survived, I guess the answer would be a hot house but then there is the hurricane season coming up.