Phoenix, Desert Botanical Gardens, AZ

Founded by the Arizona Cactus and Native Flora Society in 1937 and established at this site in 1939, the garden now has more than 50,000 plants in more than 4,000 taxa, one-third of which are native to the area, including 379 species, which are rare, threatened or endangered.

Of special note are the rich collections of agave (4,026 plants in 248 taxa) and cacti (13,973 plants in 1,320 taxa), especially the Opuntia sub-family. Plants from less extreme climate conditions are protected under shadehouses. It focuses on plants adapted to desert conditions, including an Australian collection, a Baja California collection and a South American collection. Several ecosystems are represented: a mesquite bosque, semi-desert grassland, and upland chaparral.