California Native Plant Society

State: https://www.cnps.org/

Santa Clara County: http://www.cnps-scv.org/

Plant Range Maps and Photos:

Calflora: https://www.calflora.org/

A great overall source:

Calscape: https://calscape.org/

San Francisco Bay Area Botanic Gardens:

San Francisco Botanical Garden at Strybing Arboretum: https://www.sfbg.org/

Tilden Regional Park, Regional Parks Botanic Garden: https://www.ebparks.org/parks/tilden/botanic_garden.htm

University of California Botanical Garden at Berkeley: https://botanicalgarden.berkeley.edu/

University of California, Davis Arboretum: https://arboretum.ucdavis.edu/

University of California, Santa Cruz Arboretum: https://arboretum.ucsc.edu/