Answer: There is always a lot of confusion about gardening zones. You're in USDA Zone 9 with minimum temperatures of 20 to 30?F. One of the smallest regions in the plant hardiness zone map, this mild-winter region is characterized by a long growing season and almost no winter freeze. Summers are either hot and dry or hot and humid. Although it might seem that just about any plant could do well in such a mild area, Zone 9 (and warmer) is not good for plants that require a winter chill. Those that flourish include Asparagus setaceus (Asparagus fern), Eucalyptus globulus (Tasmanian blue gum), Syzygium paniculatum (Australian bush cherry), Fuchsia hybrids (Fuchsia), and Schinus molle (California pepper tree).
There's an even better reference for gardeners on the West Coast. Sunset Western Garden Book has gone to great lengths to divide the climate zones up even further, taking into consideration elevation and proximity to bodies of water, because both can create microclimates. Your town is in Sunset's zone 19, within the thermal belt of Southern California, but with an ocean influence. Why not get a copy of the book from your local library and feast on all the information it provides? It will help you decide which plants to grow in your garden.
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