Hi Happyspirit welcome to GOY. Although we welcome non-brits don't forget that we are UK based. Tugbrethil is from your side of the pond and may want to elaborate on this but here goes:-

USDA zones are based on winter temperatures having about 10ºF difference in average winter temperature from each zone. i.e. USDA zone 8 is on average 10º warmer in winter than zone 7. I think Northern Carolina (unless my patchy knowledge of zips is wrong and you are in California) is borderline zone 7-8 BUT local micro-climates effect your own conditions a lot. Part of my garden has been specifically designed as a warm area so though I am in zone equivalent 8 that area is 9a. But if I am right about Carolina, not California, then your winter temps are about the same as most of the central slice of the UK and anything we grow, you should be OK with. It is really a matter of experience and trying things within reason. Clearly tropicals such as grow in Florida are not really on, but I used to grow, for example, citrus in pots and put them under glass in winter. So it is a case of using your ingenuity. Hope this is of some use.

Northern CA looks like 8-9 (add your zip code here http://www.completebamboo.com/bamboo_hardiness_zones.html). You have a wide range of plants that you can grow for flowers - check out what your neighbours are plant and what local stores sell and you cannot go far wrong.