The garden is a center for botanical research and science education of international repute, as well as an oasis in the city of St. Louis, with 79 acres (32 ha) of horticultural display. It includes a 14-acre (5.7 ha) Japanese strolling garden named Seiwa-en; the Climatron geodesic dome conservatory; a children's garden, including a pioneer village; a playground; a fountain area and a water locking system, somewhat similar to the locking system at the Panama Canal; an Osage camp; and Henry Shaw's original 1850 estate home. It is adjacent to Tower Grove Park, another of Shaw's legacies.
For part of 2006, the Missouri Botanical Garden featured "Glass in the Garden", with glass sculptures by Dale Chihuly placed throughout the garden. Four pieces were purchased to remain at the gardens. In 2008 sculptures of the French artist Niki de Saint Phalle were placed throughout the garden. In 2009, the 150th anniversary of the garden was celebrated, including a floral clock display.
After 40 years of service to the garden, Dr. Peter Raven retired from his presidential post on September 1, 2010. Dr. Peter Wyse Jackson replaced him as President.
The garden is a place for many annual cultural festivals, such as the Japanese Festival and the Chinese Culture Days by the St. Louis Chinese Culture Days Committee. During this time, there are showcases of the culture's botanics as well as cultural arts, crafts, music and food. The Japanese Festival features sumo wrestling, taiko drumming, koma-mawashi top spinning, and kimono fashion shows. The garden is known for its bonsai growing, which can be seen all year round but is highlighted during the multiple Asian festivals.
Linnean House (1882) – reputedly the oldest continually operated greenhouse west of the Mississippi River; originally Shaw's orangery, in the late 1930s converted to house mostly camellias
Gladney Rose Garden (1915) – circular rose garden with arbors
Climatron (1960) and Reflecting Pools – world's first geodesic dome greenhouse, designed by architect and engineer Thomas C. Howard of Synergetics, Inc; lowland rain forest with approximately 1500 plants
Seiwa-en Japanese Garden (1977) – 14-acre (5.7 ha) chisen kaiyu-shiki (wet strolling garden) with lawns and path set around a 4-acre (1.6 ha) central lake, designed by Koichi Kawana; the largest Japanese Garden in North America
Missouri Botanical Garden also operates the Sophia M. Sachs Butterfly House in Chesterfield. The Butterfly House includes an 8,000-square-foot (740 m2) indoor butterfly conservatory as well as an outdoor butterfly garden.
The EarthWays Center is a group at the Missouri Botanical Garden that provides resources on and educates the public about green practices, renewable energy, energy efficiency, and other sustainability matters.
The Shaw Nature Reserve was started by the Missouri Botanical Garden in 1925 as a place to store plants away from the pollution of the city. The air in St. Louis later cleared up, and the reserve has continued to be open to the public for enjoyment, research, and education ever since. The 2,400-acre (9.7 km2) reserve is located in Gray Summit, Missouri, 35 miles (56 km) away from the city.
Monsanto had donated $10 million to the Missouri Botanical Garden since the 1970s, which named its 1998 plant science facility the "Monsanto Center". The center has since been renamed to the "Bayer Center" following Monsanto's acquisition by Bayer.