Easy Water Conservation.
Water rates are in the news, and we are getting more interest in lower-water landscaping. It is estimated that 80% of residential water use is outside, with a very large percentage of that due to the lawn.
There are a number of easy ways to reduce your landscape water use.
First is to water correctly.
Water deeply, and as infrequently as possible for the types of plants you have chosen. For example, nothing needs water more often than twice a week during the summer here. Established shrubs and trees can often be watered once a week or less, if they get a thorough watering each time.
Most people could easily reduce their water use by 20% or more just by watering more deeply but less often.
Second is to zone your plants by water need.
You may wish to have a tropical oasis or fern grotto, so put those plants together in one area. You might want a lawn area. Your shrubs and trees don't need to be watered as often as those other types of plants.
Third is to reduce lawn area if possible.
Your lawn, properly watered, uses about 1000 gallons per 1000 square feet each week. And many people apply much more water than needed. Some turf species are more tolerant of infrequent watering, but in nearly any case the lawn is the highest water user in the landscape.
"Form follows function," Louis Sullivan said. Let your landscape form follow the actual use patterns of your family. Lawns are for kids and dogs, and are usually unneeded in front. Put lawn where you will use it, not just where you'll look at it.
Fourth is to choose plants that use less water.
For this article I'll focus on ground covering plants that can replace your lawn and use less water. First is the botanical name, then the common name if there is one. Landscape designers can choose from among Mediterranean plants, natives of South Africa and Australia, California natives, and more.
Herbaceous (soft) ground covers
* Aptenia cordifolia
Popular succulent with red flowers. Rampant! Blooms freely, smothers weeds. Bees love it. Frost turns leaves to mush, but it quickly resprouts in spring.
* Dymondia margaretae
Very tough, low-growing ground cover for dry areas. Little yellow flowers. Some die-out if overwatered. May be damaged in cold winters, but recovers. Excellent between step stones.
* Epilobium species (formerly Zauschneria)
Several species and varieties, ranging from 6" to 2'+. Bright orange-red flowers in late summer through fall attract hummingbirds. Tolerate drought or infrequent watering. Will grow in very light shade or full sun. Cut back when they look rough in the winter.
* Festuca ovina glauca
Blue or Grey fescue
Little tufts of silver grass foliage to about a foot tall. Single plants make a clump. Planted on 6 to 12 inch centers, makes an informal grey meadow.
* Gazania hybrids
G. leucoleana forms spread, have silver foliage, yellow or orange flowers. Clumping types have showier flowers, but don't cover ground as thoroughly--better in perennial borders.
* Lantana sellowiana
Lavender flowers all summer and fall; there is a less-common white form. Grows to a foot tall, with each plant spreading 6 - 10'. Very tolerant of heat and drought.
Cut back in spring to remove frost damage. Also sold as L. montevidensis.
* Rosmarinus officinalis
There are selected forms with spreading habit, and others that are upright. They vary in height (1 - 2 foot +), depth of blue flower color. All can be used in cooking.
* Sedum confusum
Dense, slow-growing succulent with shiny yellow-green leaves and showy yellow flowers. Great for edging; mix with grasses, use in pots, around stepstones. Takes sun or moderate shade, drought or average watering.
* Sedum spurium
Dragon's Blood sedum
Very low succulent grown for attractive reddish-bronze leaves. Tolerates sun or some shade; average watering or drought. Color intensifies in winter. 'Tricolor' has leaves that are white, pink, and green.
* Zoysia tenuifolia
Very dense, interestingly lumpy grass ground cover with needle-fine leaves. Dormant (brown) in winter. Very tough.
Vines that are planted as ground covers.
These are especially drought tolerant.
* Sollya heterophylla (fusiformis)
Australian bluebell creeper
Small, with dense, tiny, shiny leaves. Can be used as a ground cover. Grows slowly to about 6' tall when supported; 1 - 2' as a ground cover. Nodding blue flowers in summer; 'Alba' has white flowers. 'Boddy's Choice' is a very slow-growing type grown as a shrub or ground cover. Quite shade or sun tolerant, will grow under Eucalyptus trees.
* Trachelospermum asiaticum
Nearly always grown as a ground cover. Hardly ever flowers; grown for shiny leaves and exceptional durability. Can be tied up as a vine, but doesn't twine.
* Trachelospermum jasminoides
Super fragrant flowers in May and June. Tolerates heat, cold, sun, shade, poor soil, drought or watering.
Shrubby ground covers
There are many woody plants that spread across the ground, making a shrubby ground cover. These tend to be two to three feet high.
* Artemisia 'Powis Castle'
Vigorous spreader with silver, ferny foliage. Extremely tolerant of heat, drought; ok in partial shade. Leaves have a strong medicinal scent. Completely shades out weeds. Can cover quite an area!
* Ceanothus species
Several low spreading varieties are used as ground covers. Attractive shiny leaves; pretty blue flowers in spring. Ground cover forms range from a few inches to a few feet tall, spreading several feet. Don't plant where they'll have to be pruned. Water deeply and very infrequently in summer. California native.
* Euonymus fortunei 'Emerald Gaiety'
Low grower creeps along the ground, or can be clipped as a shrub. Very tough, tolerant of shade or sun. Flowers aren't noticeable. White portions turn pretty pink color in winter.
* Mahonia repens
Shiny leaves, yellow flowers, shade tolerant. Slow to get going, but persistent and tough.
* Ribes viburnifolium
Catalina perfume, Evergreen currant
Will grow in considerable shade. Spreads steadily to make an attractive ground cover. Fragrant foliage. Very small light pink flowers in winter attract hummingbirds; red berries attract songbirds. California native.
How to do it.
You will need to kill out your grass somehow first. You can spray with an herbicide, or cover the area with black plastic for several weeks. Get your turf species identified since some grasses can be persistent and troublesome, especially bermudagrass. The plants listed don't need any special soil preparation. Rototilling will make planting easier. But you can just dig individual holes for the small plants.
Watering of the new plantings can be done with your lawn sprinklers, but you will water far less often. Or you can convert your system to drip irrigation. You may want to ask a landscape contractor for help if you do that.
Unplanted areas can be covered with a thick mulch to retain moisture and prevent weeds. Any bark or compost product can be used. Local rock yards can deliver bulk quantities at a reasonable price.
You need to do a little math to order the right amount of mulch. For two inches of mulch on 100 square feet, you need 16.7 cubic feet (100 divided by 6 = 16.67 cubic feet). There are 27 cubic feet in a cubic yard.
Green is good, but green lawns are high water users. So reducing your water consumption often begins right in the front yard, by choosing water-thrifty plants.