Inside a greenhouse on Maryland's Eastern Shore, specialty farmer Ken Suzuki grows a small, relatively rare citrus fruit that has infatuated chefs around the world.

"Yuzu has a special smell that high-toned chefs like so much," says Suzuki, owner of Suzuki Farm, where more than 35 varieties of Japanese vegetables and fruits are cultivated. His six, 10-foot-high, seven-year-old yuzu trees yield 200 pounds of the coveted citrus per year.

"Chefs want the peel for miso soup and the juice for salad dressings and their tofu," he says. And the long list of distinctive uses for the little yuzu (pronounced YOU-zoo) goes on.

Stronger in flavor than lemon, with a hint of tangerine, grapefruit and pine, yuzu -- a hybrid of the C. ichangensis and C. reticulata species -- is native to China and Tibet. The fruit, about the size of a Mandarin orange, is commonly grown in Japan, where it's a popular culinary ingredient.

When harvested early in the season, yuzu is lime-colored, but by season's end, in late December, the fruits have turned a lemony yellow. But the demand for yuzu far surpasses the seasonal supply. So if fresh fruit is not available, yuzu lovers depend on products such as bottled juice, freeze-dried peel and prepared yuzu condiments (see box on Page F4).

Japanese cooks commonly blend fresh or bottled yuzu juice with rice vinegar, soy sauce and other ingredients for a ponzu dipping sauce for sashimi or grilled fish. The aromatic, thick, bumpy rind is grated and then added to soups and cooked vegetables.

"When you open the lid of a serving dish and the distinctive aroma of yuzu comes out, it's so delicate. There's no substitution," says Kaz Okochi, chef and owner of Kaz Sushi Bistro near George Washington University.

When whole yuzu fruits are available, Okochi hollows them and fills them with a cold lobster salad. Succulent, Nantucket Bay scallops are marinated in the juice for a ceviche. A single scoop of refreshing yuzu ice cream, accompanied by a cup of yuzu tea -- "My winter drink for Vitamin C" -- is the perfect way to end an evening at Kaz Sushi Bistro.

Chef Nobu Matsuhisa, a native of Japan with restaurants in Los Angeles, New York, Miami, Paris, London and Milan, offers more than a dozen recipes that call for this cultivar in "Nobu: The Cookbook" (Kodansha International, 2001). His signature yuzu dressing -- made with yuzu juice, soy sauce, garlic, black pepper and grapeseed oil -- is sublime atop a salad of assorted sauteed mushrooms.

But yuzu's sour flavor and exotic appeal have traveled beyond the Japanese kitchen. In Dublin, yuzu dresses a composed salad of potato and prawn. In Milan, Italian chefs whisk yuzu juice with their favorite regional olive oil as a dressing for bitter greens.

"It's more pungent than lemon and goes really well with fish. So, we use it in our tuna tartar with a yuzu mango sauce," says Thomas Keller, chef and owner of the French Laundry restaurant in Napa Valley. Yuzu makes seasonal appearances on Keller's dessert menu starring as yuzu sorbet or yuzu gelatin.

In Chicago, at the Indian-Asian restaurant Monsoon, a tandoori marinated quail salad is dressed with a splash of yuzu. Chef Norman Van Aken, owner of Norman's restaurant in the Coral Gables section of Miami, calls this fruit "the sharpest note in the keyboard of flavor." Aken marinates chicken in yuzu juice, sesame oil and tamari.

"Yuzu is so clean, bracing, the floridity. There is nothing quite like it," he says.

In New York, bartenders at boutique hotels shake or stir the yuzu martini, made with yuzu-infused sake. At the contemporary American restaurant Verbena near Gramercy Park, the nonalcoholic beverage of choice is sparkling yuzu-ade.

"People like it because it's perplexing to our flavor references," says chef and co-owner Michael Otsuka. "The yuzu taste has the sweetness of Meyer lemon as well as the sharp acidity of lime, a quality that is pretty on the palate."

Alison Chase, chef and co-owner of Aqua Terra in Annapolis, added yuzu to her menu one year ago. She uses the citrus in a ponzu sauce for pot stickers, as a dressing for a salad of daikon, cucumber and carrot and as an accent atop a grilled veal chop.

"I like to stay current with the trends. And I know [yuzu] has become really popular in San Francisco," says Chase, who shares restaurant responsibilities with her husband, Ken.

If yuzu has one drawback it is price. A single fruit, when available at Japanese markets in the Washington area, costs about $2.50. Wholesale distributors charge restaurants around $32 for a one-quart bottle of yuzu juice.

The considerable expense does not thwart chef Martin Saylor of Butterfield 9, a contemporary American restaurant in downtown Washington.

Says Saylor: "There is nothing better than yuzu, with its intense perfumelike flavor. It's really cool."

On any given day, Saylor offers dishes such as a terrific appetizer of yellowtail sashimi with yuzu sorbet, a rich entree of bison osso buco in a sauce of fermented soy bean and yuzu juice and a beautiful yuzu tart with blackberry sauce and ginger syrup.

But not every dish is an immediate success.

On a recent afternoon, Saylor and his sous-chef, Brandon Child, set their sights on a new yuzu-inspired entree. The proposed components: broiled lobster, a yuzu-flavored zabaglione and "pearl" couscous. At hand are half a dozen assorted yuzu preparations that include yuzu juice as well as pure and flavored yuzu peel purees and powders. The whisking and blending begins.

Some minutes later, the chefs raise forks. Then, Saylor takes a bite. "That's potent stuff. We should have gone with a little less yuzu," he says.

Child takes a bite. "If ever there was a work in progress, this is it. Let's ditch the zabaglione and go with a reduced yuzu juice with butter -- a yuzu beurre blanc," he says.

Work on this dish will continue -- but only in the Butterfield kitchen. "We never experiment on guests," says Saylor.

But yuzu is not limited to the kitchen.

On the evening of the winter solstice, in keeping with a tradition that is believed to encourage health, many Japanese enjoy a hot yuzu bath. Fruits bob on the surface. Yuzu is an of-the-moment ingredient in candles, as well as bath, fragrance and beauty products.

In a widely reported item, actress Sandra Bullock and "Chicago" star and Oscar nominee Renee Zellweger had their famous faces cleansed with an extract of yuzu in preparation for the Golden Globe awards. No doubt, with every squeeze, yuzu's star rises.

At Butterfield 9, chef Martin Saylor prepares a yuzu and passion fruit soup with a sauce of rambutan, a spiny Asian fruit. "There is nothing better than yuzu, with its intense perfumelike flavor," Saylor says.At Butterfield 9, chef Martin Saylor likes to experiment with yuzu.