Keiko and Frank Wells of Westfield Farm are best known for their avocados, which Keiko, with a gentle smile, carefully classifies by ripeness at the Beverly Hills farmers market. For a few months in late summer and in fall, however, they also sell sudachi, a lime-like Japanese citrus related to yuzu, but smaller, juicier, less seedy and slightly more acidic. With a distinctive spicy aroma evoking lime, pepper, dill and cumin, it is used to flavor soups, fish dishes and matsutake mushrooms. Unlike yuzu, the juice, rather than the rind, is most prized.

Sudachi, like yuzu, is a cross of mandarin and ichang papeda, a primitive citrus kin to kaffir lime. Japanese farmers cultivate hundreds of acres of sudachi in Tokushima prefecture, not far from Osaka, where Keiko was born.

Until recently, sudachi was rare in California, but about five years ago the trees became available at local nurseries, and Keiko and Frank planted some at their farm in Camarillo. They now sell the fruits for the modest price of $3 a container. As in Japan, they usually harvest sudachi when it is green and about the size of a pingpong ball, because that's when its flavor is strongest, but they also bring some in autumn, when it is larger and bright yellow.

Another maverick farm, Mud Creek Ranch of Santa Paula, has 30 sudachi trees and occasionally brings the fruits to the Santa Monica market on Wednesdays and the Hollywood farmers market, where chefs and brokers snap them up, co-owner Robin Smith says.

Tips of the week: Emerald Beaut plums, sweet, juicy and firm, from Ken Lee at Torrance and South Pasadena; moist, almost translucent, rutab-stage Halawy dates, tasting like caramels, grown by the Bautista family, at Long Beach Marina, Hollywood and Culver City; new-crop Okinawan sweet potatoes with purple flesh, from Tony Chu in Torrance.

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