Gardening in the Dunes
San Francisco is a city of sand. When I arrived here over 35 years ago my first garden was in a flat in the Sunset District. I recall thinking, “Will anything grow in all this sand?” The answer happily, is an unqualified yes! While many still believe our sand dunes are barren there are many native plants that grow and thrive here.
Why So Much Sand?
Several millennia ago, the Pacific Ocean’s relentless action and the erosion of the Sierra Nevada brought granite sand into the bay creating sand dunes. Over time, with the help of prevailing westerly winds and rising sea levels, the sand advanced inland. As much as a quarter to a third of San Francisco was once covered in sand. The sand dunes were stabilized by deep-rooted vegetation, creating a diverse native plant community supported by insects, birds, reptiles, and mammals. You can still see coastal dune scrub communities at Fort Funston (the largest remaining sand dune field), up above Baker Beach, and at Hawk Hill near Golden Gate Heights.
How Cool are Dune Plants?
Dune plants commonly have small, waxy, hairy, and/or succulent leaves, and deep root systems that allow them to survive in dry, nutrient-poor sand. Not to mention they can withstand blustery salty winds! For an example of great coastal dune plantings visit Land’s End near the old Sutro Baths.
What to Grow?
The San Francisco Plant Finder database (http://sfplantfinder.org/) notes at least 41 plants suitable for dunes or sandy soil. You can find many of these hearties at Bay Area native plant nurseries including the Sutro Stewards Native Plant Nursery. For more information about our nursery including volunteer opportunities, see http://sutrostewards.org/page/nursery.
Here are some samples to get your native habitat garden growing:
Seaside Daisy (Erigeron glaucus)
Perennial herb, grows 1-3 feet; pink-lavender flowers with fuzzy green leaves bloom winter through summer. Friendly to bees and butterflies. Great for coastal gardens and has lots of blossoms. They’re easy to care for, needs low watering, and are popular in landscaping as a ground cover.
Coast Buckwheat (Eriogonum latifolium)
Perennial, grows 1-3 feet, blooms in the summer. Birds, bees, butterflies and insects love them. Blue and green hairstreak butterflies especially like buckwheat and many of these species suffer from dwindling habitat. Buckwheat flowers seem to last forever, turning a chocolate color in the fall. They are very drought tolerant and can survive many arid environments.
Yellow Bush Lupine (Lupinus arboreus)
Evergreen shrub, grows 4-6 feet, yellow flowers blooms May to August. A friend to bees, butterflies, and hummingbirds. This native of the Pea Family has smooth, green, hairy, palmate leaves (resembling the palm of your hand). The erect stems have dense, yellow flower clusters and pod like, brown-black fruit. Lupines have the ability to fix nitrogen into soil.
Lizard Tail (Eriophyllum staechadifolium)
Perennial in the Asteraceae (sunflower) family, grows 1-3 feet with lovely yellow blossoms appearing May through August. Supports bees, butterflies and insects. It is a shrub that is highly drought, salt, and wind-tolerant; hence it is perfect for coastal environments.
Sea Thrift (Armeria maritima ssp californica)
This perennial species has spherical clusters of tiny, funnel-shaped, light to dark pink flowers on stems 10 to 14 inches high with short, slender grass-like leaves in mounds. Blooms spring to summer in coastal areas. It’s deer resistant and can grow in full sun or partial shade.
Dune Tansy (Tanacetum bipinnatum)
Perennial herb in the Asteraceae (Sunflower) family. Flowers are yellow disc florets with leaves that are lacy and ferny. It’s aromatic with a camphor-like scent. Blooms summer through December. Easy to care for and commonly used as a ground cover.
Gum Plant (Grindelia hirsutula)
Perennial herb belonging to the Asteraceae (sunflower) family. Blooms from July to September. Tough, dependable and fast growing, they are long-blooming plants perfect for a drought-tolerant garden. They provide quality food for bees, butterflies, and birds. They’re good on hillsides for erosion control and are also deer-resistant.
References:
San Francisco A Natural History. Greg Gaar and Ryder W. Miller. 2006. Arcadia Publishing.
SF Bay Area National Parks Science and Learning, Coastal Dunes. http://www.sfnps.org/dunes
http://sfplantfinder.org/ San Francisco Dept. of Planning; San Francisco Dept. of the Environment
Sand Dunes. Nat’l Park Svc, GGNRA, https://www.nps.gov/goga/learn/nature/sanddunes.htm
Seaside Fleabane. California Native Plant Society.http://calscape.org/Erigeron-glaucus-(Seaside-Fleabane
Yellow Bush Lupine. Nat’l Park Svc. Presidio of San Francisco.https://www.nps.gov/prsf/learn/nature/yellow-bush-lupine.htm
The Gumplants (Grindelias), Michael Wood; Yerba Buena Chapter of the California Native Plant Society (CNPS); September 1996. http://www.cnps-yerbabuena.org/experience/focus_on_rarities.html?ju...
Armeria maritima ssp californica http://www.calfloranursery.com/plants/armeria-maritima-ssp-californica
Coast Buckwheat. Nat’l Park Service, Presidio of San Francisco.https://www.nps.gov/prsf/learn/nature/coast-buckwheat.htm
Eriophyllum staechadifolium. Lizard tail. http://www.calfloranursery.com/plants/eriophyllum-staechadifolium
Dune Tansy. Tanacetum bipinnatum. California Native Plant Society Calscape. http://calscape.org/Tanacetum-bipinnatum-(DuneTansy)?srchcr=sc57c7b6084a8f2