The United States Botanic Garden is located across from Capitol Hill on the National Mall in downtown Washington D.C., near Garfield Circle. The Botanic Garden is a truly green spectacle, with a jungle, a First Ladies water garden, a rose garden and exhibits on ecology and evolutionary biology. The Garden is composed of three adjoining sites which are the Conservatory, the National Garden and Bartholdi Park. All areas are free of admission and are open from 10 AM to 5 PM except Bartholdi Park which is open from dawn to dusk.

This is the oldest continually operating botanic garden in the United States. The proposal for the establishment of the United States Botanic Garden dates back to 1816. From 1820 to 1837 it functioned to the west of the Capitol. In 1850 it reinitiated at that site after a number of plants were brought back from a South Seas expedition. In 1933 the current site became the home of the Garden. Since 1934 the Architect of the Capitol is responsible for the operation and maintenance of the Garden. In 1842, Charles Wilkes returned from the ?United States Exploring Expedition? with a massive collection of plants previously unknown to the United States. This garden was ultimately built to house those plants. Within the garden today, there are still four plants that are believed to either be the actual plants from the expedition or their descendents.

The United States Botanic Garden Conservatory is a window to the world. Its exhibits span 150 million years, the range of global environments, as well as botany, economy and culture. Constructed by the architect of the Capitol in 1933, this historic Lord & Burnham greenhouse contains eight garden rooms under glass, totaling 28,944 square feet of growing space. In 2001, the Conservatory re-opened after a four-year renovation that required it to be completely dismantled and rebuilt for the 21st century.