San Francisco — At the corner of 22nd and Irving Streets, Joe stopped repiling the oranges at the produce market, leaned over his handcart, and picked up a reddish-brown oval pod. With his pocket knife he peeled off the prickly skin, sliced one piece off, then ate that and the rest - including the cream-colored core, the tiny dark inside seeds, and the lime-green drippings.
Customers stopped to watch. Joe winked. ''Good,'' he said, ''good for lunch, good anytime.''
The curious, reading the kiwi fruit sign above the bin, asked, ''What's it taste like?''
Joe shrugged. ''Some say grapes, some say strawberries, some say melons, some say rhubarb. It's your guess.''
It's not much of a guess anymore for thousands of American consumers who are buying the fuzzy kiwis in their local markets. Once regarded as just another exotic import from New Zealand, the bug-resistant kiwi is fast developing into an important US farm product. The kiwi, introduced around 1937 at the Plant Introduction Station run at Chico, Calif., by the US Department of Agriculture, is now grown on about 1,000 commercial farms in the state.
California growers originally took on the kiwi as a secondary crop - sometimes combined with peach orchards. Getting started in the kiwi fruit business is expensive: Steps include vineyard preparation, adequate pollination, drip irrigation, frost control, pruning, and vine training. But market development and grower efficiency have made California farmers the nation's largest producers of the fruit.
As an out-of-the-ordinary profitmaker, kiwi is attractive to growers. On today's market, kiwis bring orchard prices of about $1.50 to $2 a pound, versus other crops like peaches which go for 3 cents a pound. Although still a minor crop, in 1980 the egg-shaped pod returned California growers over $13 million; and with the rapid expansion of plantings, the 1981 total ran to about $18 million.
Demand in world markets for kiwi appears to be growing faster than production. At present over 80 percent of New Zealand's crop (the world's largest) as well as that of California is exported to other countries - Japan and Germany are big buyers. Analysts for the California Kiwi Commission estimate that at the present rate of demand for the product, world production will have to increase 13 times just to meet the future potential in the United States.
Growth in consumer preference has been based on the fruit's sweet-tart taste, which has been compared to no less than 15 other soft fruits. Home economists are quick to point out other attributes besides taste. It is high in vitamins and minerals (twice the vitamin C of a large orange) and has a low calorie count. Kiwis keep for weeks under home refrigeration. Food page editors are turning out more and more recipes using the fruit as a garnish, in salads, as dessert combinations, and as a snack.
Kiwi grows commercially on deciduous vines (similar to some grapes) spread out on pergola-like T-bars. It needs protection from wind and standing-water soil but likes high humidity and sunshine - conditions found today in Butte County of north central California and 32 other counties of the state. The vines are high climbers that flower in April, producing fruit until the September-October harvest.
Although a shy bearer in early years, the vine offers excellent future per-acre production possibilities. State agriculturists point out that the Chico ''mother vine'' at 45 years of age is still a vigorous producer.