One of the crowning jewels of Sand Diego is Balboa Park, a 1200-acre expanse overlooking downtown San Diego.  Once the park, as well as most of San Diego, was mostly barren.  But not today.  The beautiful botanical gardens of the park are the work of a pioneering woman, horticulturist Kate Sessions, known as the “Mother of Balboa Park.”

Katherine Olivia Sessions was born in San Francisco on November 8, 1857 (died 1940).  Like her mother, she became an avid gardener, plant collector and flower arranger.  She graduated from the University of California, Berkeley, in 1881, having studied chemistry and agriculture.  Following the usual path of educated women of her time, she became a teacher and moved to San Diego.

Her interest in plants never left her, however, and she left the schoolroom to go into the nursery and flower business with friends in 1885.  Her business flourished, as did her reputation as a botanist and landscaper.  In 1892, she formed a partnership with the City of San Diego in which she acquired rights to use a 32-acre tract within what was then called City Park as a plant nursery.  In exchange, she was required to plant 100 trees annually in City Park and supply 300 trees for other municipal lands.  That partnership lasted for a decade and began the lush landscape that the park—renamed Balboa Park in 1915—is known for.  

Much of the lush vegetation of Balboa Park owes itself to the work of Kate Sessions (photo by Fastily)

Sessions began to travel extensively—trips to Hawaii, Mexico and across Europe—to observe plants in their native environments and bring home seeds and specimens for introduction into the gardens of San Diego.  Many of the largest and oldest trees still surviving in Balboa Park were planted personally by Sessions (today, she gathers some criticism for having introduced non-native plants to southern California, but she also provided habitat for several rare Mexican species that might have disappeared without her intervention).

She was a founding member of the Sand Diego Floral Association and helped create the first Arbor Day in the city in 1904.  She was a prolific author, speaker and educator about plants, gardens and landscape architecture.  For decades, she taught horticulture to public school children and personally managed the landscapes around public schools in San Diego.  In her commercial nurseries, she grew test plots of species and cultivar for the U.S. Department of Agriculture.  She won the Frank N. Meyer Medal of the American Genetic Association in 1939 for her work in plant introduction.

Sessions will always be most closely associated with Balboa Park.  In 1935, at the California Pacific International Exposition held in the park, she was formally crowned with the loving title of “Mother of Balboa Park.”  The park hosts nearly 5 million visitors each year, half of whom are local residents who use the park on average ten times per year—that makes over 25 million visitor days per year, generating an economic impact of $350 million annually.

Statue of Kate Sessions in Balboa Park (photo by Right Cow Left Coast)

I’m reminded of the sentiment by Margaret Mead, never to doubt that a few dedicated people can change the world.  Kate Sessions certainly changed hers, and ours, through the living joy of plants.


Balboa Park.  Balboa Park History.  Available at:  Accessed March 2, 2022.

Carter, Nancy Carol.   About Kate..  Available at: Accessed March 2, 2022.

San Diego History Center.  Kate Sessions 1857-1940.  Available at: Accessed March 2, 2022.

San Diego Natural History Museum.  Kate Sessions.  Available at:  Accessed March 2, 2022.

Testa, Mark R., et al.  2017.  Balboa Park Benefits Study.  San Diego State University.  Available at:  Accessed March 2, 2022.

This Month in Conservation

September 1
Martha, the last Passenger Pigeon, Died (1914)
September 2
President Roosevelt Dedicated Great Smoky National Park (1940)
September 3
Wilderness Act passed (1964)
September 4
Fort Bragg, Home of Red-cockaded Woodpeckers, Established (1918)
September 5
UNESCO Established First World Heritage Sites (1978)
September 6
Alcide d’Orbigny, French Naturalist, Born (1802)
September 7
Edward Birge, Father of Limnology, born (1851)
September 8
UN Millennium Declaration ratified (2000)
September 9
First “Bug” Found in Computer (1945)
September 10
Henry Hardtner, Father of Southern Forestry, Born (1870)
September 11
World Wildlife Fund Began Operations (1961)
September 12
Canyonlands National Park Established (1964)
September 13
Walter Reed born (1851)
September 14
Marc Reisner, Author of Cadillac Desert (1948)
September 15
Darwin reaches the Galapagos Islands (1835)
September 16
Ed Begley Jr., Environmental Advocate, born (1949)
September 17
Edgar Wayburn, Wilderness Advocate, Born (1906)
September 18
Grey Owl, Pioneering Conservationist in Canada, Born (1888)
September 19
Urmas Tartes, Estonian Nature Photographer, born (1963)
September 20
AAAS Founded (1848)
September 21
Assateague Island National Seashore Created (1965)
September 22
Peace Corps becomes law (1961)
September 23
Rose Selected as U.S. National Flower (1986)
September 24
President Kennedy Dedicated Pinchot Institute (1963)
September 25
Pope Francis Addressed the UN on the Environment (2015)
September 26
Johnny Appleseed Born (1774)
September 27
“Silent Spring” Published (1962)
September 28
National Public Lands Day
September 29
Steinhart Aquarium opens (1923)
September 30
Hoover Dam Dedicated (1935)
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