Fallbrook, like most other locales, has microclimates. We have very seldom gotten frost on our property in 28 years and yet a couple of acres away, the house at the end of the road has a low spot along the road that's a cold pocket that regularly gets hit with frost and bananas, etc. freeze. A friend's house two miles away cannot grow the plants that I do. If you're buying, try to take a look around the neighborhood and see what's growing, etc. A good slope with southern exposure helps also. We live in the 'Winterwarm' area...called that for good reason. A lot of variation in the Fallbrook area due to the hills and canyons.

Previous post offers excellent advice. I am growing Cantua buxifolia here(a long way north of San Diego). I bought it years ago as a four inch pot with no idea of what it was. When you shop Annies Annuals it could be anything! It only blooms on old wood and here old wood is hard to come by as it frosts back every year. It is a sturdy plant that comes back from the roots, so I am just going to wait for global warming to kick in. Al

You might visit the Quail Gardens in Encinitas to see samples of plants that grow in our region. The comment about micro climates is pertinent. My cherimoya and avocados in the back yard don't freeze, but bougainvillea in the front yard does freeze.

Here is a link that might be useful: Quail [renamed SD] Botanical gardens