Since it was established in 1974, the Smithsonian Gardens Orchid Collection (SGOC) has grown from five plants to over 6,000 specimens from all over the world. Collections like SGOC are a vital conservation resource offering protection to species from a variety of threats including habitat change and over collecting. Orchid collections can also form the basis of reintroduction and restoration programs aimed at helping improve the conservation status of orchid species in the wild.

Smithsonian Gardens holds the third largest species-diverse collection in the world. New acquisitions are selected carefully each year based on their display quality, educational value, beauty, rarity, and how they complement the present collection. SGOC is an invaluable resource for scientific research, educational programs, and exhibitions. It is maintained in the Smithsonian Gardens Greenhouse Facility in Suitland, Maryland by staff, interns, contractors and volunteers.

In 2014, SGOC was designated a Nationally Accredited Plant Collection by the American Public Gardens Association and recognized by the Association as a Plant Collections Network Collection of National Significance.