San Diego Floral Association in downtown San Diego's Balboa Park has promoted horticultural education from its headquarters in the Casa del Prado since its founding in 1907 as a spin-off from the Chamber of Commerce. The association's library of more than 3,500 indexed volumes and its complete archive of California Garden magazine — published continuously since 1909 — make it a botanical research resource on par with the living collections maintained by San Diego Zoo Wildlife Alliance across the park. Founded by first president A.D. Robinson, whose lath-house experiments with begonias inspired the Botanical Building that remains Balboa Park's most photographed structure, the association played a central role in beautifying San Diego for both the 1915 Panama-California Exposition and the 1935 California Pacific International Exposition. Its Festival of Trees exhibition during Balboa Park's December Nights event and its quarterly general assemblies draw from a membership base of more than 2,000 gardeners, and its docent-led garden tours coordinate with the concert programming at Spreckels Organ Society for cross-promoted park visits along El Prado. The association's most complex ongoing project is maintaining and expanding the California Garden archive, a 115-year continuous publication record that documents the horticultural transformation of a desert coastal city into one of the most botanically diverse urban regions in North America.