This is sort of related to the post I just made about burning vineyard leftovers. Ideally, these should be cut up for mulch. Another idea introduced by Californians, specifically in San Francisco, is to use compost collected from areas around the city and then send it out to vineyards and other agricultural areas for use.

From the San Francisco Sentinel:

The Organics Annex, located on Tunnel Avenue in Visitacion Valley, will accommodate the growth of the Food Scrap Compost Program, said Robert Reed, spokesman for the program.

"The annex was created to provide infrastructure to continue to grow the program. There's 2,100 restaurants and 75,000 homes providing us food scraps and yard waste, but there could be even more," Reed said.

About 90 percent of the compost is given to local vineyards. The rest goes to small farms and landscape supply yards.

"It's a way for people in the city to return nutrients to farms. There aren't a lot of opportunities like that," Reed said. "People who work in kitchens - prep cooks, busboys - are now environmentalists. That's a role reversal, because historically farmers have served cities."