Help for the Gardener from the Contra Costa Master Gardener Help Desk
Client's Request: I am looking for advice on a drought tolerant grass variety or mix for my front yard. We are located in San Ramon, and the area receives full sun. We have taken out our existing lawn! We will have edibles, water permeable surfaces, paths and a small amount of grass (or other suitable ground cover), about 200 ft2. This will be mostly ornamental, although one area (next to the driveway) will likely receive some foot traffic. I identified UC Davis Buffalo grass as a possibility, but we are open to anything that makes sense. Most important are low water requirement and low maintenance, ability to tolerate some foot traffic, open to a longer ‘shaggy' growth habit, although the ability to mow to a shorter length would be nice. Full sun environment. Soil is good I think, some clay but not too heavy, drains well.
CCMG Help Desk Response: Congratulations on taking the first step towards a water-wise garden by removing your lawn. It's important that we all learn how to use water more efficiently as demand rises and drought conditions continue. You would like to retain a small lawn which will receive foot traffic next to the driveway and would like advice on grass selection.
Before evaluating lawn alternatives, it is important to understand the differences between the two categories of grasses. Grasses are considered warm-season or cool-season, depending on when they grow best. In California warm-season grasses (e.g Bermuda, St. Augustine, buffalo) generally do best in southern California while cool-season grasses (e.g. blue, rye, fescue, bent) do best north of the Bay Area. In between is a transition zone, where both cool-season and warm-season grasses will grow but the climate is not optimum for either. Warm-season grasses tend to turn brown and go dormant during the winter in areas where there is frost, such as San Ramon. And cool season grasses require extra water to endure our hot dry summers.
Below are several options for lower water use grasses which can tolerate foot traffic. However, none of the grasses listed below currently qualify for your Water District's (EBMUD) lawn conversion rebates, nor does synthetic turf. In order to qualify for a lawn conversion rebate, EBMUD requires that the lawn be replaced with low or very low water-use plants, or permeable lawn alternatives such as decomposed granite or mulch.
Native Bentgrass - Agrostis pallens is a cool-season California native bentgrass, with a uniform growing habit, medium texture, and deep green color. Native bentgrass requires full sun, withstands foot traffic, and has a good wear recovery due to self repairing rhizomes. Native bentgrass can be either mowed or it can be left to flop, creating the look of a natural, informal meadow. If you want the look of a mowed lawn, you should continually mow it. If you let it get long and shaggy before mowing it low, it will have a scalped look until it has had time to grow back. The sod grower's irrigation trials indicate that Native Bentgrass requires about half the water of a traditional cool-season grass to keep the lawn green throughout the year. Starting a native bentgrass lawn from seed can be a challenge because it is slow to start. But it has recently been made available as sod with degradable netting from Delta Bluegrass Company in Stockton. The price of Native Bentgrass sod is more than that of traditional blue, rye, or fescue sods because it takes longer for the grower to produce. If cost is not the primary factor, a Native Bentgrass sod might make a great alternative to your conventional lawn. For more information on this California Native Sod, see http://www.deltabluegrass.com/blendcomparisonchart .
UC Verde Buffalograss - UC Verde is a variety of buffalograss which was developed by University of California researchers at Riverside and Davis as a lower water use alternative to the traditional cool and warm-season grasses. It is a warm-season grass native to the North American plains; it looks terrific during summer; and is soft on bare feet. But its main drawback is that in Northern California it goes fully dormant in the winter, turning straw-colored after a hard frost occurs. People often use a biodegradable green dye during the winter in order to maintain the appearance of a green lawn. UC Verde grows to only 4-6" tall and requires mowing only every 2-3 weeks. It is planted from plugs which are usually spaced 12 inches apart and should be planted early in the warm season (e.g. May) to give the lawn a chance to establish before the weather cools. It spreads by rhizomes and is very competitive with weeds once established. However, keeping the lawn weed-free until it becomes fully established is more challenging than installing sod, and may require an aggressive weeding campaign. UC Verde buffalograss requires 50% to 75% less water than the typical fescue lawn. For more information on growing and maintaining UC Verde buffalograss, including photos of the grass throughout the season, see http://cesacramento.ucanr.edu/Pomology/Turf_Demonstration_Project/Three_species_in_irrigation_trial/UC_Verde_buffalograss/ .
No-Mow Fineleaf Fescue – Fineleaf fescues are cool-season grasses which include red fescue, Chewings fescue, sheep fescue and hard fescue. Many new and improved fineleaf fescue species and cultivars have come to California in recent years. Fineleaf fescues can be either seeded or sodded. They typically require about 85% of the water needed to keep a typical lawn green in the summer but they can withstand more severe irrigation deficit and dormancy with the ability to come back the following year. Fineleaf fescue lawns can be kept to about 2 ½" by mowing every 2 to 3 weeks or they can be left to grow to a height of 6 to 12 inches to create a "natural" look by mowing 1 to 4 times per year. They are an aesthetically pleasing no-mow grassy groundcover, with lower water requirements, however, they are not suitable for areas where pedestrian traffic is common. For more information on fineleaf fescue, see the attached U.C. article "No-Mow Fineleaf Fescue Grasses for California Urban Landscapes" (http://anrcatalog.ucdavis.edu/pdf/8391.pdf).
Irrigation – Whichever grass you select, your irrigation system plays an important role in water conservation. Standard spray irrigation heads are not an efficient method of applying water. You might consider replacing conventional sprinkler nozzles with high-efficiency rotating or precision nozzles. Or perhaps install a below grade inline emitter system such as Eco-mat by Hunter irrigation http://www.hunterindustries.com/irrigation-product/micro-irrigation/eco-matr-and-pld-esd . Replacing traditional irrigation timers with weather-based models (smart controllers) can help to provide the amount of water actually required by the plant, and often results in water savings. If you are redoing you irrigation system, you might want to check out the water district's rebates, if any, for upgrading irrigation equipment and installing Smart Controllers (for EBMUD see http://www.ebmud.com/for-customers/water-conservation-rebates-and-services/lawn-conversion-irrigation-upgrade-rebates).
Good luck with your project. Feel free to contact us if you need additional information.
Contra Costa Master Gardeners' Help Desk
Note: The Contra Costa Master Gardener Help Desk is available year-round to answer your gardening questions. Except for a few holidays, we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 75 Santa Barbara Road, 2d Floor, Pleasant Hill, CA 94523. We can also be reached via telephone: (925) 646-6586, email: firstname.lastname@example.org, or on the web at http://ccmg.ucanr.edu/Ask_Us/