The arboretum is a series of gardens and fountains with a view of the lake and the downtown Dallas skyline. The majority of the grounds were once part of a 44-acre (18 ha) estate known as Rancho Encinal, built for geophysicist Everette Lee DeGolyer and his wife Nell. Mrs. DeGolyer's interests included her extensive flower gardens. The DeGolyer Home is listed on the National Register of Historic Places. Since 1976, the DeGolyer estate has formed the largest portion of the Dallas Arboretum & Botanical Gardens. The addition of the adjoining Alex and Roberta Coke Camp estate increased the size of the grounds to sixty-six acres.
The 21,000-square-foot (2,000 Sq mi) Spanish-style DeGolyer Home was completed in 1940. The DeGolyer Garden Cafe/Loggia, located at the back of the DeGolyer Home, overlooks White Rock Lake and the tiered fountains and formal landscapes of A Woman's Garden. Also located on the grounds is an outdoor concert stage, picnic areas, and set of kid size replicas of dwellings and other structures depicting prairie life in the "Texas Pioneer Adventure."
In September 2002, Arboretum facilities were expanded with the opening of the new visitors Center named for Dallas developer Trammell Crow. The center consists of a gift shop, meeting room, gazebo, and a patio area overlooking WhiteRock Lake. At night, one may view downtown Dallas with the skyscraper lights reflecting upon the water. The gazebo is named for Gisela Rodriguez and was financed in part by donations from her son Marcos A. Rodriguez.