The Rhododendron Species Foundation and Botanical Garden in Federal Way, Washington, is a nonprofit woodland garden devoted to rhododendrons, with more than 10,000 plants across roughly 22 to 24 acres. Founded in 1964 by members of the American Rhododendron Society, it grew from a small propagated collection that moved from Oregon to Washington in 1974. The garden emphasizes conservation, research, cultivation, and distribution as much as display, and has become one of the world’s major centers for rhododendron species. Its holdings include hundreds of species from around the globe, tropical vireyas in the Rutherford Conservatory, and additional themed garden areas, while field research and scientific study remain central to its mission.