Boerner Botanical Gardens, on the grounds of Whitnall Park in Hales Corners, Wisconsin, developed in the 1930s as part of the wider creation of the Milwaukee County park system. Named for designer Alfred Boerner, the gardens began with five formal sections: Annual, Perennial, Rock, Rose, and Peony. Their construction was made possible in part by Depression-era federal labor programs, including the Civilian Conservation Corps and the Works Progress Administration, amid limited county funds. Charles B. Whitnall, Alfred Boerner, and longtime director John Voight were central to its founding and growth. The site later expanded with additional specialty gardens, display areas, and an arboretum extending into nearby parkland.