South Mill Champs

South Mill Champs traces to 1932, when Louie Pia began operating a small mushroom farm in southeastern Chester County. The Pia family became the region's largest supplier of growing substrate and began selling fresh mushrooms under the South Mill name in 1982. Between 2017 and 2020, South Mill merged with growers in British Columbia and Manitoba to form South Mill Champs, one of the largest mushroom producers in North America, and in 2022 it opened a roughly 300,000-square-foot single-site farm near Oxford.