Greenfield (formerly, Clarke Colony) is a city in Monterey County, California, United States. Greenfield is located 33 miles (53 km) southeast of Salinas, at an elevation of 289 feet (88 m). The city was the fastest growing in the county during the 2000s, the population was 12,583 in 2000, increasing to 16,330 in the 2010 census. Its most well-known public event is the annual Harvest Festival. Greenfield is a member of the Association of Monterey Bay Area Governments.
John S. Clarke and other promoters laid out the town from 1902 to 1905 on part of the Rancho Arroyo Seco Mexican land grant. The original name of Clarke City was rejected by the post office which established Greenfield post office in 1905. Greenfield incorporated in 1947.
Greenfield traces its roots to 1905 and the creation of Clark Colony Water Company, which built a network of irrigation canals and filled them with water from the nearby Arroyo Seco AVA. Greenfield's central location makes it a "springboard" to a number of Southern Monterey County attractions. There are plans on building a museum on Greenfield's history. Construction is said to start in 2008 or 2009.