Answer: There always seems to be confusion about gardening zones. I'm cautious about using the USDA zones because they seem to be so broad in interpretation. So, I rely on the Sunset Western Garden Book to pinpoint my zone. Sunset takes into consideration elevation, proximity to bodies of water, etc., all of which can create microclimates. According to Sunset's book, Tehachapi is in their zone 1A, with winter lows averaging from 0 to 11F and extreme lows of -25 to -40. If you are a lower elevation, you might fit into their zone 7 where typical winter lows range from 23 to 9F and extreme lows have been recorded at 15 to -1F. It's always best to choose plants which can endure the lowest average temperatures that your garden experiences. Check out a copy of Sunset Western Garden Book at your local library or garden center. You can find your town on the maps and then look up plants according to the zone Sunset has assigned to you. You'll come away with a list of appropriate plants that will grow and thrive in your garden.
Hope this clarifies things for you!
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