The Hillsborough Garden Club is committed to supporting the communities of San Mateo County through contributions to various environmental organizations, public gardens, schools, parks and museums.

Club members have been actively involved with projects such as the Marilyn Hills Memorial Garden that graces the front of Crocker Middle School in Hillsborough; hands-on invasive species eradication at local natural land preserves; planting and maintenance of the traffic island at Hayne Road, a primary entrance into Hillsborough; and planting gardens at Alcatraz, Coyote Point’s Wildlife Center, Hillsborough’s Town Hall and San Mateo’s Arboretum. 

The club participated in the Garden Club of America's 2013 Centennial Tree project by planting 28 oak trees at Coyote Point, the peninsula’s most visited park. Several times a year the members create seasonal baskets to cheer up residents in local care facilities.