Although young, Rain and River Anderson, are no strangers to working on a farm.

Their mother, Molly Anderson of Petaluma, said her daughter Rain, 5, and son River, 3, help feed the family's ducks and chickens at home.

On Monday, the family, including 6-month old Reef in a harness on Anderson's back, spent their Martin Luther King Jr. holiday volunteering at Petaluma Bounty's community farm.

The older siblings loaded child-size wheelbarrows with mulch from a pile, pushed them over to a grassy area, unloaded and spread the dark ground cover around.

The Andersons were among about four dozen volunteers who, in the King spirit of "a day on, not a day off," helped with seasonal duties at the nonprofit farm.

"Most people have the day off, but we wanted to come and help out," Anderson said. "I'm teaching these guys at a young age that it's fun to volunteer and be part of a bigger community."

The federal holiday marking the birthday of King was created in 1983. In 1994, Congress designated the holiday as a national day of service and charged the Corporation for National and Community Service with leading the effort.

In Petaluma, that translated to a beehive of activity at the farm on Shasta Avenue off Petaluma Boulevard North.

Farm manager Lennie Larkin pointed the glove-wearing volunteers toward projects to make compost, pull weeds, prepare beds for spring planting, fertilize the 100 or so fruit trees and more.

Petaluma Bounty is a nonprofit community farm formed in 2006 with a goal of providing healthy, local food at low cost to the community.

Every April, it holds a plant sale, its major fundraiser. Much of Monday's prep work was to get the farm ready for spring crops.

Many of those volunteering were from service groups, including Rotaract, a youth Rotary club, and high school students fulfilling community service requirements. Others were completing court-ordered volunteer time, said project manager Suzi Grady.

Phoebe Vernier Caceres and her husband, Alfredo, specifically sought out a King day of service event to volunteer for.

"Sometimes you need a special occasion to inspire people," she said. "And this day is inspiring."

You can reach Staff Writer Lori A. Carter at 762-7297 or