By Tish Berge, CNPS Garden Ambassador
As residents throughout the county consider removing their turf with the help of rebates offered by our Southern California water utilities (more information at https://socalwatersmart.com/en/residential/rebates/available-rebates/turf-replacement-program/), it’s a good time to remember that there are native grasses that have many benefits, from low water use to high habitat value.
Ornamental grasses are one of 11 plant categories being highlighted as part of the California Native Plant Society’s statewide campaign to boost the sale of California native specialty crop plants by 20% in volume over the next 3 years. The campaign—Bloom! California: Native Plants for a Bright Tomorrow—is funded by a California Specialty Crop Block Grant and is the first project of its kind in the state. For more information, see Native Plants for a Bright Tomorrow - BLOOM! CALIFORNIA for the announcement that came out during California Native Plant Week and https://bloomcalifornia.org/ for the website with more information on how to participate. Bloom! California is in Phase 1 and is recruiting partners who own, operate, manage, or work for a California-based nursery or retailer. If you know someone who fits that category, please share this information with them!
Here are all 11 selected plant groups: Ornamental Grasses, Mints, Iris, Currants, Clarkia, Manzanita, Yarrow, Sage, Phacelia, Toyon, and Oaks. Each of these types of plants contributes differently to the garden from both an aesthetic perspective and a wildlife and habitat perspective. When I punch in my ZIP code on Calscape (https://calscape.org/), I get no fewer than 85 different grass species, of which I have four in my yard. Several ornamental grasses are listed on Bloom! California, and this article will highlight some that perform well and are well-suited to San Diego.
DEERGRASS. Let’s start with deergrass (Muhlenbergia rigens), a large perennial bunch grass. It likes full sun and grows quickly to 4–5 ft tall and 4 ft wide. In spring it will create cream-colored flower spikes that can reach up to 5’ and attract seed-eating birds in summer. According to Calscape, “Deergrass is one of the most beautiful and probably the easiest to grow of all the native California bunchgrasses, typically reaching mature size in one or two years.” Noting its large size, it will do better in gardens with ample space. While it likes sandy or gravelly soil, it is tolerant of any soil as long as it is well drained. In my yard, it has survived in my clay soil and dry streambed. From a gardening perspective, the deergrass in my yard is used in two ways: (1) as a formal low hedge, and (2) in the dry streambed. Against the house, the soft form of the grass softens the space between the concrete driveway and the stone siding. I regularly prune this grass to create uniformity with regard to size and form. I’ll discuss pruning methods later. In the dry streambed, the grass not only softens the rock bed, but also filters the water that flows in the bed when it rains. It’s common after a rain to see piles of leaves caught by the grass. The grass does not reseed easily, so it won’t take over your garden, though some gardeners have found it popping up in various places in their garden over the years. The bunches can get rather large and benefit from occasional division, at which point you can relocate the extra plants to another spot in the yard or give them to neighbors. The best time to divide is winter, and it will require a sharp spade to cut through the dense clump and fibrous roots. While the seeds support birds, the plants themselves provide shelter for sleeping bumblebees and burrowing squirrels and rabbits (who may dine on the young plants), but they bounce back quickly from the free pruning. (Source: http://sonomamg.ucanr.edu/Plant_of_the_Month/Muhlenbergia_Rigens/). Calscape suggests using larger plants as companion plants, including several listed on Bloom! California: Toyon (Heteromeles arbutifolia), lemonadeberry (Rhus integrifolia), larger ceanothus species, manzanita species, or scrub oaks.
WILD RYE. Wild rye (lymus conEdensatus), is a medium grass with silver blue-green foliage. The individual blades of grass are wider than those of deergrass. It likes full sun, is evergreen and clumping, and grows to 3–6 feet tall by 2–8 feet wide. The width comes from the ability of the plant to spread by rhizomes, but with its moderate growth rate, it is easy to contain if that is your preference. The flower spikes are brown and can reach several feet above the height of the grass. It supports butterflies and moths, and the seeds can be eaten by mammals and birds. Calscape suggests using these companion plants: Bush sunflower (Encelia californica), California sagebrush (Artemisia californica), coyotebrush (Baccharis spp.), oaks, sages (Salvia spp.), and buckwheats (Eriogonum spp.). In my garden, I have found this plant to be smaller in scale and more sparse (not as dense of a clump) compared to my deergrass. The seed stalks are striking and beautiful when they happen. From a garden perspective, its color is a great asset and adds variety to the landscape.
SEDGE. While not on the Bloom! California list, one of my favorite grasses is sedge (Carex spp.). In my rain garden (“rain garden” is a fancy way of saying “the part of my yard that gets wet-weather runoff from the house”), I have clustered field sedge (Carex praegracilis). This grass brightens after the rains, provides food for the rabbits, and offers a soft place to lie for the dogs. It grows just a couple feet tall by a few feet wide. In the dry season, it will yellow and fall over. Sometimes I prune it, sometimes I don’t, and it spreads easily by rhizomes. Those seeking a lawn alternative that still provides a turf look can use this grass, as it has a soft texture, can be mowed, and requires significantly less water (source: https://calscape.org/).
On my hillside, I let the grasses grow without pruning, and that is where the squirrels and rabbits have burrowed. Near the house, I prune them. Pruning grasses typically involves cutting them to the ground in what might be referred to as a “hard” prune. When I prune my grasses, I try to get as close to the ground as possible, typically leaving just a few inches. The best time of year to prune is fall.
Other grasses from Bloom! California that grow well in San Diego include:
California brome grass (Bromus carinatus)
Blue wild rye (Elymus glaucus)
Purple three awn (Aristida purpurea)
Meadow barley (Hordeum brachyantherum)
One sided blue grass (Poa secunda)
Junegrass (Koeleria macrantha)
Melicgrass (Melica californica and Melica imperfecta)
Alkali sacaton (Sporobolus airoides)
Needlegrass (Stipa lepida and Stipa pulchra)
For more inspiration from CNPS Garden Ambassadors, visit https://www.cnps.org/tag/garden-ambassadors .
Tish Berge, Native Garden Committee Co-chair has been a CNPS member since the early 2000s when she got her very first native plant, a Catalina Cherry. She likes natives because they are drought tolerant and attract wildlife. She recommends workshops, tours, and patience to new gardeners.