The Oak Spring Garden Library comprises a collection of over 16,000 objects, including rare books, manuscripts, and works of art dating back to the 14th century. It is the legacy of horticultural icon Rachel Lambert "Bunny" Mellon, and helped inform her gardening design, including the White House Rose Garden.

The Oak Spring Garden Foundation's mission is to perpetuate and share Mellon's gifts, including her residence, garden, estate, and the Oak Spring Garden Library, to serve the public interest. OSGF is dedicated to inspiring and facilitating scholarship and public dialogue on the history and future of plants, including the culture of gardens and landscapes and the importance of plants for human well-being.