The Year of the Rooster will not start to crow until next week, but preparations are already well under way to welcome the Lunar New Year.

“It used to be every night for two weeks before and two weeks after New Year’s Day, there would be a couple of celebrations. Now there are five or six a night for the entire two weeks before and the two weeks after,” a City Council member, John Liu, said, ticking off New Year’s celebrations from a parade along Flushing’s Main Street to a gathering along Staten Island’s Mosel Avenue by that borough’s burgeoning Chinese population.

“It’s a massive exercise in time management and also appetite management,” Mr. Liu said.

Chinese-Americans, the city’s second-largest immigrant group, have spread far beyond their initial landing pad in Lower Manhattan. So have the New Year’s celebrations.

Each of the city’s three Chinatowns – in Manhattan, Flushing, and Sunset Park – will hold parades the weekend after the February 9 New Year is celebrated. The Lunar New Year is not only a Chinese holiday, with other countries, including Korea, Malaysia, and Vietnam, joining in the festivities.

“There are larger numbers of people and a different layering of immigrants,” the executive director of the Museum of the Chinese in the Americas, Charles Lai, said, describing how celebrations have shifted. “People are also bringing in the culture that had evolved in the home countries, whereas here the evolution of culture is much slower.”

The example of a lag in cultural evolution, Mr. Lai said, is the Lunar New Year Flower Market, which the museum launched in Manhattan’s Chinatown last year. “For people who have been here in this country at least 10 to 15 years, the tradition was not known to us, whereas it is a very important one in the home countries,” he said.

Now New York is following the trend, with immigrants buying flowers at an outdoor market on the weekend before the New Year. The flowers represent prosperity, and celebrants choose the most auspicious varieties to adorn their homes, like peach and plum blossoms, peonies, and dahlias.

While the public face of the holiday is the marching-lion dances, the fireworks, and the moon cakes, the lunar New Year is traditionally a private celebration.

“On Chinese New Year, usually you stay home, and on the eve, you eat a dinner like Thanksgiving, with family,” the president of the Better Chinatown Society, Steven Tin, said. “We celebrate by eating, eating, and more eating.”

Mr. Tin, who is organizing the Manhattan parade, expects upward of 250,000 spectators and 100 groups participating, more than ever before.

Publicity got a boost this year with the city’s tourism agency, NYC & Company, launching an initiative to promote Chinatown.

Along Sixth Avenue at Sunset Park, Brooklyn, where more than 20,000 Chinese immigrants live, the parade won’t compare with Manhattan’s in size, but organizers expect roughly 20,000 spectators to attend.

The Flushing parade, directed by a collaboration of local Chinese and Korean business associations, is also growing. “Every year we have more people than the previous year,” the president of the Flushing Chinese Business Association, Peter Koo, said. But even with 50 different groups parading, Mr. Koo said the Flushing event is much smaller and less commercial than its Manhattan counterpart. “We are just a celebration for local people,” he said.