Answer: Loquat is generally hardy only to USDA Zone 8, and you're squarely in zone 7. Since it's potted, you can probably keep it small by limiting the pot size, and this will allow you to move it to a sheltered location for the coldest months. Another option is to train it as an espalier against a wall in a sheltered location, where it will neither freeze nor put out tender growth when winter thaws occur. Ideally, winter temperatures should not dip below 40F at night, and should reach no more than 55F during the day.
Repotting is necessary only in the first few years. Provide a well-drained soil and keep soil evenly moist. Refresh the top layer of soil yearly with rich compost (when not repotting), and fertilize regularly during seasons of active growth, especially after the tree's roots fill the pot. Enjoy this living piece of your California past!
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