About the Garden

Studying, exhibiting and conserving California native plants for more than 85 years.

Rancho Santa Ana Botanic Garden (RSABG) is the largest botanic garden dedicated to California native plants.

The Garden

Spread across 86 acres in Claremont, California, the Garden is located approximately 35 miles east of Los Angeles. Nestled in the foothills of the San Gabriel Mountains, the Garden offers beautiful mountain vistas.

The Garden displays about 2000 taxa of California plants and includes those native to the California Floristic Province as a whole. This region extends into southern Oregon, far western Nevada and extensively into Baja California, Mexico. Docents lead tours of the Garden periodically. Guidebooks and brochures are available at the California Garden Shop.

The Garden is laid out in three distinct areas. Indian Hill Mesa is a large flat-topped hill of dense clay soils, heavily planted with mature cultivars and wild species of native plants. Some of the most prominent species are wild lilacs and Manzanitas. The mesa is home to the California Courtyard, California Natives Container Garden and California Cultivar Garden—three of our popular venues for social and business events. The East Alluvial Gardens are found at the base of the eastern edge of the Indian Hill Mesa include the Desert Garden and the Coastal Dune and California Channel Islands collections. The Tongva Village interpretive site and the Majestic Oak are both located in the Alluvial Gardens. The northern 55 acres is home to the Plant Communities with displays of some of our most impressive specimens in the entire collection. The large serene groves of Four-needled Pinyon, the spring-blooming California Flannel Bushes and distinct boojum trees are found here.


Conservation Programs

RSABG conservation programs play a major role in saving species and protecting natural habitats for future generations. Four constituents comprise the Conservation Botany Program—the Seed Conservation Program, plant growth facilities, field studies and laboratory studies. For more information, please contact Naomi Fraga, RSABG conservation botanist, at This email address is being protected from spambots. You need JavaScript enabled to view it..

Facilities and Programs


Documentation of the flora of California is ultimately based on scientifically made collections that are housed in herbaria designed to store dried plant specimens—and the information that they represent—in perpetuity. RSABG is the 10th largest in the United States. Our facilities hold more than a million specimens, almost half of which are California plants. Approximately a quarter of these specimens have been digitizes and the records are served online through the pooled site of the Consortium of California Herbaria. 

Living Collection

Rancho Santa Ana Botanic Garden maintains an extensive living collection of tens of thousands of plants. A majority of these specimens are field collected from wild sources and all are documented in a secure database. The Living Collection supports horticultural research and trials to discover and propagate genotypes of native plants that are especially suited to the Southern California home landscape. The Living Collection along with the Seed Conservation Program makes RSABG the largest ex-situ conservation effort for California native plants.

Four RSABG constituents comprise the Conservation Botany Program—the Seed Conservation Program, plant growth facilities, field studies and laboratory studies. Please contact our Research Department for more information about these important aspects of RSABG’s mission.

Seed Conservation Program

Properly collected, vouchered, stored, and curated seeds are widely understood to serve as a biological insurance policy for our native plant heritage. The primary function of RSABG's Seed Conservation Program is the curation and management of the RSABG’s extensive seed collection. The collection is comprised of over 3,000 accessions representing more than 1,600 California native plant species and cultivars. These collections serve a diverse community in the conservation, botanical, research, education and horticultural fields. RSABG’s Seed Conservation Program is part of the U.S. National Seed Bank initiative of the Center for Plant Conservation. Staff undertakes a variety of activities to build and safeguard the collection.


A world-class botanical library, the RSABG Library supports the Botany Program and is open to the public. The library contains approximately 48,000 volumes and 750 journals and periodicals. The collection is searchable through The Claremont Colleges online catalog http://blais.claremont.edu


As a scientific research organization and institution of higher education, RSABG is involved with research in systematic and evolutionary botany (science fields that sort out the relationships and evolutionary history of plants).

RSABG provides formal graduate-level education and community education programming. Affiliated with The Claremont Colleges, RSABG trains professional botanists through a graduate education program with degrees granted by Claremont Graduate University.

Encouraging the use of California native plants in home landscapes is a major aspect of our objective and to further this goal, we offer horticulture and community education programs to the public. The Garden’s grounds include many areas designed to illustrate the ways in which native plants can be used to achieve home garden and landscape design projects. From docent lead tours of the Garden to community education workshops, RSABG offers many opportunities designed to help visitors gain a greater appreciation for native plants.


Our major facilities include: RSABG Administration Building and Plant Science Center, Research and Horticulture Complex, Lee Lenz Horticulture Building, Lantz Outdoor Classroom, California Courtyard and California Natives Container Garden.

Accreditation and Associations

RSABG is accredited by the American Alliance of Museums (formerly the American Association of Museums), and is an institutional member of the American Public Gardens and Arboreta, the Association of Systematics Collections, the Center for Plant Conservation, the California Association of Nurserymen, California Garden Clubs, Inc., the Claremont Community Coordinating Council and the Claremont Chamber of Commerce.

Rancho Santa Ana Botanic Garden is a private, non-profit, tax-exempt California charitable trust.