The Loma Prietan - March/April 2009

Gardening Green

Green Your Lawn with Native Grasses

by Arvind Kumar

A native lawn of Pacific dune sedge looks lush with just monthly watering. Photo: Sustainable Landscape Designs & Curtis Horticulture
A native lawn of Pacific dune sedge looks lush with just monthly watering. Photo: Sustainable Landscape Designs & Curtis Horticulture

Now we know that California is in its third consecutive year of drought. This winter and the previous two have been drier than normal. Our reservoirs are well below capacity, the rivers are running low, and water districts have been uttering the C-word with increasing frequency — yes, they are finally talking about water conservation.

Wildlife and ecosystems are stressed, because they must share a dwindling water supply with us humans. But, judging from the lush lawns in neighborhoods and the sprinklers watering the sidewalks in office parks, it seems we are in denial about the looming water crisis.

If there ever was a good time to reduce our water consumption, it is now. More than half the water used in suburban homes goes to watering the lawn. Why not lose the lawn, cut the water bill in half, and help the environment, all in one fell swoop?

In January, I attended an inspiring talk on native grasses by David Amme, president of the California Native Grasslands Association. Amme is a font of knowledge on California's native grasses, with years of experience in propagating and planting. What he has found is that many of these grasses work just as well in home gardens as they do in the wild.

Amme advocates replacing traditional lawns with native grass meadows. Because the native grasses are deep-rooted and longlived, they play a vital role in converting carbon dioxide into plant tissue and sequestering it deep into the soil. The grasses come in a variety of attractive colors and textures that can enhance your garden.

There are two broad types of grassland for our area: the coastal prairie and the foothill grassland.

Coastal prairie conditions are sunny and mild, with fog and cool breezes. Here you find California oatgrass (Danthonia californica), a plant that doesn't mind being stepped on; or red fescue (Festuca rubra), a grass that expands by underground rhizomes; or Pacific dune sedge (Carex pansa), a lush green groundcover.

Foothill grasslands are warmer and drier. They are dominated by cool-season bunchgrasses that are green in the winter and tan during summer. These include purple needlegrass (Nassella pulchra), Idaho fescue (Festuca idahoensis), nodding needlegrass (Nassella cernua), California melic (Melica californica), pine bluegrass (Poa secunda), and foothill sedge (Carex tumulicola).

Late fall is the best time to plant a native meadow, and Amme recommends that you begin preparing in summer. Remove the lawn and prepare the soil so it is not compacted. Water the area so that weed seeds germinate, then remove the weeds before they go to seed, and water again. Repeat the process a few times until the weed seed bank is exhausted. By the start of the rainy season, the area will be weed free and ready to plant. Planting from seed is most economical, but if your budget allows you can plant from plugs. Make sure to irrigate regularly, especially during periods of no rain.

Establishing a water-wise, mature meadow takes a few years. Amme does not recommend mixing in annual wildflowers, which grow much faster than the grasses and shade them out. Instead, he suggests allowing the grasses to grow by themselves the first year, and introducing perennial wildflowers in the spaces between the bunchgrasses the second year. The perennials can include: checkerbloom (Sidalcea malviflora), California buttercup (Ranunculus californicus), yarrow (Achillea millefolium), Douglas iris (Iris douglasiana), blue-eyed grass (Sisyrinchium bellum), and hummingbird sage (Salvia spathacea).

Vary the irrigation schedule and the mowing height to control your mix of grasses and flowering perennials. Frequent watering and low mowing encourage creeping grasses like red fescue at the expense of the flowering perennials. Reduced watering and higher mowing encourage foothill grasses as well as flowering perennials.

There are native grasslands nearby from which you can draw inspiration. The website of the California Native Grasslands Association (www.cnga.org) contains a list of 11 grasslands, each with photos and directions (click on "Guide to Visiting California's Grasslands").

Grasslands are complex ecosystems, rich in habitat value. Establish your own, and bring nature in all its subtlety to your doorstep. Conserve water and reduce your water bill. Green that lawn in the best sense of the word.

Sierra Club life member and California Native Plant Society director Arvind Kumar grows native plants in his Evergreen garden. He can be reached at chhaprahiya@yahoo.com.