“I don’t know if it’s going to be the youthful, happening Woodstock they want it to be, but it certainly has the potential,” said Corby Kummer, a food columnist, book author and Slow Food board member. “It will be a failure if it is only well-dressed people over 35 from the Bay Area treating it as if it’s another Ferry Plaza Farmers Market”  a reference to the place where well-fed San Franciscans and celebrity farmers chat over perfect peaches and soft, ripe cheese.

Carlo Petrini, a charismatic Italian who writes about food and wine, started Slow Food with friends who shared his notion that left wing politics and gastronomic pleasure could be happily married. The international organization has grown to 86,000 members and become an industry in Mr. Petrini’s hometown, Bra, Italy. There are Slow Food restaurants, a university and a hotel. You can buy a cashmere truffle-hunting vest embroidered with the Slow Food snail logo at the main office in Bra.

Image Kaylah Frazier watering plants at the Civic Center Plaza in San Francisco. Credit... Jim Wilson/The New York Times

The group’s budget is about $39 million, and subsidized by the Italian government. Much of the organization’s work involves identifying traditional foods, like Ethiopian white honey or Amalfi sfusato lemons, and designing ways to help the people who produce them.

Its philosophy  that food is about much more than cooking and eating  is often hammered home by Mr. Petrini on his frequent trips around the world.

“I always say a gastronome who isn’t an environmentalist is just stupid, and I say an environmentalist who isn’t a gastronome is just sad,” he said through an interpreter in an interview last year.

In the late 1990s, Mr. Petrini’s ideas were quickly embraced by people on America’s coasts who were fans of farmers’ markets, local food and a slower, more reflective way of life. Ms. Waters, who had spent more than two decades advocating delicious organic food and the small farms that grew it, was among them.