Ben Naman and Alli Adams work with medicinal plant species in greenhouses at the San Diego Botanic Garden.

Since 1970, the verdant San Diego Botanic Garden has inspired and educated plant lovers, from casual enthusiasts to seasoned horticulturists alike. Located at the Encinitas-Leucadia border, the landscape offers visitors an interdisciplinary and international journey among gardens, nurseries and greenhouses, restoration habitats, research facilities, and more. Four miles of accessible paved and earthen trails meander through 29 gardens, representing 15 regions of the world and 5,300 plant species and varieties. Many of these are types on which humanity greatly depends: medicinal plants.

San Diego Botanic Garden (SDBG) acknowledges and invests in research and project development in both Western scientific and traditional ecological knowledge (TEK) ways of knowing, stewarding, and using plants. This includes medicinal plants across many human cultures and contexts. By one definition per the International Union for Conservation of Nature and the World Wildlife Fund, there are between 50,000 and 80,000 species of medicinal plants worldwide. Medicinal plants can be taken in a variety of ways, including in solid form by eating whole or in a preparation; in liquid form as a beverage such as a tea or extract; applied topically in balms, salves, and poultices; or in vapor form as an inhaled or ambient steam or smoke. Some continue to be used in these fundamental forms, while many others have taken the shape of common pharmaceuticals that support our health and well-being in Western medicine.

Linking departmental staff, project design, funders, key partners, and stakeholders, SDBG’s Science and Conservation Department and its projects are guided by three main pillars: medicinal plants, native and rare plants, and food and agricultural plants. Indeed, as many plants provide multiple ecological and cultural services, they often are categorized as serving several functions.

Two key staff members in the Science and Conservation Department are Colin Khoury, PhD, senior director of science and conservation, and C. Benjamin (Ben) Naman, PhD, director of medicinal plants research. They each bring international experience and a deep appreciation for the Garden’s opportunities to practice research, collaborative conservation, and community outreach. An exciting departmental project, per SDBG’s website, is the “creation of a national medicinal plants collection and research consortium to catalyze drug discovery in San Diego and beyond.” Part of this project includes “creating a medicinal plant demonstration garden and implementing educational programming to teach visitors and community members about medicinal plants used in traditional medicine, plant-derived Western medicines, and related medical innovation.”

Early written records of medicinal plants include those found in an ancient Sumerian (c. 3000 BCE) description of Papaver genus poppies, the predecessor to today’s opioid pain relief drugs (Merck’s morphine, 1826), and Salix genus willow’s salicylic acid for skin care and acetylsalicylic acid, also for pain relief (Bayer’s aspirin, 1899). Our contemporary lives are filled with plant derivatives that have become products in Western medicine, health, and wellness markets. Oral histories from Indigenous traditions predate written traditions since time immemorial.

Referencing expansive statistics and counting the world’s medicinal plants, including many worthy local candidates, SDBG is taking an investigative approach with depth rather than breadth. Focusing research on relatively few important species, including those pertinent to San Diego County’s First Nations (Cahuilla, Cupeño, Kumeyaay, and Luiseño) and many others, two stand out in terms of cultural significance and investment of research:

Yerba Santa.

YERBA SANTA (Eriodictyon spp.)

• Preparations include teas and poultices for cold and pain symptoms, among others

• Kumeyaay names include variations on samalh

California sagebrush (also known as cowboy cologne).

CALIFORNIA SAGEBRUSH (Artemisia californica)

• A variety of preparations include external and internal applications for everything from wounds to illnesses and digestive issues

• Kumeyaay names include variations on chimpilh

Working collaboratively, SDBG accomplishes both rigorous science and extensive and meaningful outreach. “We’re really just community building,” says Dr. Naman, referring to not only community-based restoration work at schools and on public lands, but also work with the 15-plus consortium member organizations including large institutions and start-up companies (Salk Institute for Biological Studies, Ionis Pharmaceuticals), higher educational institutions (University of California San Diego, Cal State University San Marcos), and tribal and affiliated entities. Special acknowledgments are also due to Dr. Stan Rodriguez, EdD, board director and professor at Kumeyaay Community College, and Lisa Cumper, tribal historic preservation officer at Jamul Indian Village.

The Local and Native Plants Garden at San Diego Botanic Gardens is surrounded by rare coastal sage scrub and southern maritime chaparral with features that demonstrate Kumeyaay living.

Medicinal plants bring healing to our bodies, minds, and communities, and ecosystems have always been a significant factor in our well-being. SDBG’s efforts and their collaborators help to ensure this reality endures. Blending a deliberate and thoughtful balance of research, community, and donor development results in innovative programming, and San Diego Botanic Garden cultivates an environment of both plant and cultural diversity, all dedicated to environmental and human flourishing.


The information in this article is for educational purposes only and is not intended to diagnose, treat, cure, or prevent any disease.

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About the Contributor
Colin H. Richard
Colin H. Richard is an educator and storyteller active in environmental, sustainability, and community development issues in Southern California and internationally. He is a graduate student in social innovation at the University of San Diego’s Joan B. Kroc School of Peace Studies. Colin brings 20+ years of experience in regenerative agriculture, conservation, and tourism with a regional focus on East Africa. Learn more at