Article by Pam Muick

Coast live oak is a native, evergreen oak emblematic of coastal California. It grows throughout Solano and Yolo counties.  Generally growing no further than thirty miles of the coast, it is a fast-growing and statuesque species. 

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All oaks are keystone species due to the many resources they provide. Besides acorns, coast live oak’s evergreen leaves protect and provide food for many species, from insects to mammals to birds, in the winter when deciduous oaks have lost their leaves.

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In this series, we have compiled a short list of compatible native plants you can consider in developing a native plant garden around your Coast Live Oak.  Native plant species are grouped by form:  grasses and bulbs, wildflowers, and short and tall shrubs. All of those listed are available at native plant nurseries and/or California Native Plant Society sales. CalScape is an excellent reference to use for learning about and locating plants to buy. 

Another special attribute of Coast Live Oak is the oak leaf mulch produced from fallen leaves. Instead of removing fallen leaves, consider allowing them to remain under the tree to create a deep natural mulch.

When evaluating your plant palette, consider native species that thrive in DRY SHADE. Note that most deep-rooted plants should be planted several feet away from the tree trunk, some even as far out as the edge of the tree’s canopy.

Grasses and Bulbs: Native perennial grasses do well in dry shade. Low-growing perennial grasses include Torrey’s Mellicgrass (Mellica torreyana), and California Fescue (Festuca californica).  Beautiful native bulbs enjoying this space are Golden Globe lily (Calochortus amabilis), Ithurial’s Spear (Triteleia laxa) and Iris (Iris species). 

Wildflowers: In nature, elegant Clarkia (Clarkia unguiculata), Chinese Houses (Collinsia tinctoria) and Fivespot (Nemophila maculata), Western Houndstongue (Adelinia grandi) – not the invasive species - do well on the edge of Coast live oak canopy.

Small perennial plants and shrubs will thrive along the canopy edge.  Included in this group are yarrows (Achillea species), coyote mint (Monardella sheltonii), Hummingbird Sage (Salvia spathacea), Mugwort (Artemisia douglasiana) and Columbine (Aquilegia formosa). This is a good location for snowberry (Symphoricarpus albus).

My favorite tall shrub is Ocean Spray or Creambush (Holodiscus discolor). It is the host plant for a number of butterfly larvae, including Lorquin's admiral, pale tiger swallowtail, and spring azure butterflies. 

Spreading Ground covers: wild strawberries (Fragaria), California fuchsia, hummingbird sage, lower-growing varieties of Yarrow (Achillea millefollium) and coyote mint (Monardella species)

Would you like online help with a plan? https://bayarea.calscape.org/wp-content/uploads/2022/10/111022_Woodland-1.pdf

Resources

How to Grow California Oaks
https://oaks.cnr.berkeley.edu/how-to-grow-california-oaks/

Growing Oaks from Acorns
https://ucanr.edu/sites/ccmg/files/123756.pdf

Planting Under Oaks, UC Master Gardener Program of Sonoma County
http://sonomamg.ucanr.edu/Planting_Under_Oaks

California Oaks, a project of the California Wildlife Federation
https://californiaoaks.org/

https://ucanr.edu/site/uc-master-gardener-program-contra-costa-county/article/gardening-under-oaks

For more information, please visit the Oak section of the UCANR IPM website at ipm.ucanr.edu, the californiaoaks.org website