By Rebecca Jepsen for the Mercury News November 13, 2009
Conserving water is becoming increasingly important as we enter our fourth year of drought in Santa Clara County.
There is also a lot of buzz about water-wise gardening, xeriscaping and environmental responsibility. According to Kevin Galvin, senior water conservation specialist with the Santa Clara Valley Water District, more than half of our residential water is used on landscaping, and the runoff of toxic chemicals and fertilizers into our water system is very high.
We Americans love our lawns, and although that perfectly mowed, lush green lawn is the epitome of beauty for many homeowners, it has many inherent costs. We spend money to purchase and maintain our mowers, edgers and blowers, not to mention the fuel required to run them. The environmental cost of toxic emissions emitted by the equipment also needs to be considered. According to the Save20 gallons.org Web site, we can save 20 gallons of water a day by replacing just 1,000 square feet of lawn with better, water-wise options.
Fall is the best time to replace your lawn, but before you embark on removing your lawn, it's helpful to know what you are working with. Some lawns are easier to get rid of than others.
Sheet mulching, or smothering, the lawn is effective for most types of turf. Apply a layer of cardboard or newspaper over your lawn (being sure to generously overlap the edges) and cover with a three-to-four-inch layer of mulch.
If, like many homeowners, you have Bermuda grass, you may need to take more drastic measures. Use a sod cutter, which will cut the Bermuda grass roots at approximately three inches or more, flip the cut sections over to let them die off. You may need to sod cut repeatedly to completely eradicate Bermuda grass.
John Greenlee, a California nurseryman and an expert on ornamental grasses and sedges, says using a "grow and kill" cycle is the most effective way to get rid of existing turf, especially Bermuda grass. Carefully apply Round-up (per instructions) on your healthy lawn, cut all water for a period of one to two weeks. Reapply water and wait for new growth, repeat previous step. You may need to repeat the cycle two or three times, but Greenlee says this is the most efficient method.
There are many water-wise, low maintenance, and beautiful replacement options to consider.
Sedge lawns Sedge lawns most closely resemble normal turf lawns. With proper selection and planting, a sedge lawn will function much like a traditional lawn, but with a lot less water and mowing. Sedges, part of the Carex genus, come in a variety of sizes from miniature to several feet tall. They can be used in sun or shade and in almost every climate zone.
An excellent option for the Bay Area is the California meadow sedge (Carex pansa). It is a fast-growing variety with dark green foliage that will grow to only about 4 to 6 inches if left unmowed. It can be planted in either full sun or part shade. Plugs can be planted directly into your sheet mulch. Cut holes 6 to 12 inches on center, loosen the roots of the plugs, and add a couple of handfuls of soil (planting mix or top soil) as you go.
With proper irrigation — once a week near the coast; more often in hot climates — your new lawn should fill in within a few months. Once established, it will need to be mowed only about three times per year. However, make sure the blades on your mower are very sharp so you don't damage the plant by fraying its edges.
For shady areas, try Texas sedge (Carex texensis). If you are planting under an oak, leave a 5-to-10-foot radius unplanted to avoid disturbing the root zone of the tree.
Eco-lawns Ecology lawns or eco-lawns can be planted from seed. They are usually a mixture of native and non-native grasses, herbs and flowers. The exact mix will vary depending on supplier and planting conditions. Eco-lawns grow about four times more slowly than normal turf lawn and therefore require only one-quarter the amount of mowing. Because of their extremely long root system, they need very little water once established and no fertilizer.
Meadow lawns Meadow lawns not only provide visual diversity year-round, they can also provide much needed habitat for birds, butterflies, bees and bugs. You can create a meadow lawn by planting a mix of native grasses and fescues, yarrow and other wildflowers. They can be planted from seed or plugs. It's important to weed out invasive grasses such as wild oat, Italian rye and foxtails while the meadow gets established. Shady options include: California Fescue (Festuca californica) with wildflowers such as Douglas Iris (Iris douglasiana), Western Hound's Tongue (Cynglossum grande), Yarrow (Achillea millefolium), California poppy and Sky Lupines (Lupinus nanus).
Herb lawns For a nice-smelling alternative, try planting an herb lawn. Before selecting a variety to use, it's important to consider your planting conditions. For sunny areas try Roman Chamomile, yarrow or Golden or Variegated Oregano. Shade-loving options include Sweet Woodruff or Yerba Buena, which grows naturally under oaks.
Herb lawns can't take heavy foot traffic, so you may want to include steppingstones or create a pathway. Periodic hand-weeding is recommended. Most herb lawns don't need to be mowed; however, you may want to weed-whack the yarrow periodically.
Master Gardener Gretchen Zane contributed to this report. The Santa Clara County Master Gardener Program is a volunteer organization dedicated to providing research-based gardening information to home gardeners. Have a question? Call the hot line, 408-282-3105, from 9:30 a.m. to 12:30 p.m. Mondays through Fridays. Or visit the Master Gardeners Web site at www.mastergardeners.org.
Ripping out your entire yard may not be possible or practical; start with a section on your lawn or landscape that is in need of repair and "grow" from there. You may want to experiment with a few varieties to see what you like and what will grow well in your specific environment.
Most of the varieties listed here can be found at Bay Area nurseries: Native Revival (www.nativerevival.com); East Bay Wilds (www.eastbaywilds.com); Rana Creek Nursery (www.ranacreeknursery.com); or online at Greenlee & Associates (www.greenleeandassociates.com) or Bay Natives (www.baynatives.com).
To find out about more ways to save water or to learn about the Landscape Rebate Program, contact the Santa Clara Valley Water District hot line at 408-265-2607, or check www.valleywater.org.