Katherine Olivia Sessions graduated from the University of California, Berkeley in 1881 with a telling graduation essay: "The Natural Sciences as a Field for Women's Labor." She came to San Diego to teach, but then began a series of business ventures beginning with the San Diego Nursery and continuing with several additional nurseries in the San Diego area. She gained a reputation, both statewide and nationally, for her horticultural expertise, particularly landscaping, plant introductions and classes. She published numerous articles, helped found the San Diego Floral Association in 1906, and was appointed supervisor and teacher of agriculture and landscapes for city schools in 1915. Sessions� experiments with plant introductions won her the 1939 Frank N. Meyer medal from the American Genetic Association�the first woman to receive this prestigious award. However, San Diegans, past, present, and future, owe a true debt to Sessions for her creation of Balboa Park.
She leased land in 1892 for a nursery in "City Park" where she began planting 100 trees a year. She also planted at least 300 more throughout the city. She helped create a Park Improvement Committee to ensure the long-term survival of her landscaping. The Tijuana Tipu tree planted by Kate Sessions at the site of her nursery at Garnet and Pico in Pacific Beach is now a California Registered Historical Landmark. The bronze statue of Kate Sessions guarding the entrance to Balboa Park at the Laurel Street Bridge is the only full sculpture in the city dedicated to a real-life woman, the "Mother of Balboa Park."