Xeriscaping is the practice of landscaping with slow-growing, drought tolerant plants to conserve water and reduce yard trimmings. From the beginning, a landscape can be designed to reduce the amount of resources needed to maintain it and the amount of waste it produces. Each region of California has different resource conditions, such as available water, soil type, temperature ranges, and lighting. When beginning a landscape project, consider the intended use. By designing a landscape in an appropriate manner, selecting compatible plants, and installing efficient irrigation systems, a balance can be achieved that fits both the aesthetic needs of the landowner or client, and the resource availability of the region. Thoughtful landscape design will also lead to long term savings in maintenance time, reduce expenses and be beneficial to the community.
Many times a landscape is “inherited”–it is already established and you are simply charged with maintaining it. A transition to a more resource-efficient landscape may be a possibility through evaluating the existing habitat and deciding what to remove or add to the space.
California’s limited supply of water, subject to ever increasing demands, is just one resource saved by xeriscaping. This results in immediate cost savings through lower water bills. Xeriscaping can reduce the amount of plant trimmings which must be disposed of or otherwise managed, thereby helping your community, and ultimately you, to save resources. A reduction in plant trimmings can reduce the amount of labor needed to maintain a given landscape. Or, put another way, reduced plant maintenance allows more time to be spent on other aspects of landscape maintenance, or on another landscape account.
Xeriscapes generally require less fertilizer and fewer pest control measures than traditional landscapes. Because pesticides and fertilizers can inadvertently harm beneficial organisms, as well as impact air and water quality, reducing their use is a good idea. And, of course, using less of these materials saves money.
Landscape Design and Plant Selection
The practice of xeriscaping will vary from region to region within California. Plants which are appropriate in one climate may not work well in another. The moist northwest may even be considered inhospitable to sturdy plants of the desert south. Landscapes need to be planned to be compatible with locally available resources, including water, soil types, and sunlight. Native plants are typically available at local plant nurseries. In addition, the California Native Plant Society has over thirty-five chapters across the state and resources that can help you start gardening with native plants according to region.
Today’s waste-efficient landscapes use “unthirsty” plants–California natives and drought tolerant exotics. Proper soil preparation, garden layout, and planting time assures that plants can mature into beautiful specimens with minimal trimming. In a word, the modern approach to California landscaping is xeriscaping.
While California native plants are naturally accustomed to local climates and therefore good choices for water and waste efficient landscapes, xeriscaping can incorporate other appropriate plants. For example, one could draw from many available colorful drought tolerant plants native to other “Mediterranean” climates such as Southern Europe, North Africa, Western Asia, South Africa, and Australia. There are many excellent books that provide further information on this subject, as well as a growing number of nurseries that specialize in xeriscape plants.
Soil Preparation and Irrigation Systems
Healthy soils grow healthy plants. A well drained soil, generally defined as one that can absorb a 1/2 inch of water or more per hour, creates a good environment for grass, plants, and trees to set deep roots and take advantage of deep water and nutrients. In the long run this makes for healthy, steady growth with reduced fertilization and irrigation needs. Of course a soil can be too well drained, such as a sandy soil, and need some help to better hold water and nutrients for plants.
The addition of the proper soil amendments can either help a soil drain faster or slower. Well composted organic material is an ideal amendment that can serve both these purposes. Additionally, a good compost provides a source of slow release nutrients for plants. The balanced growth encouraged by these conditions can reduce pruning maintenance as well as disease and pest pressures.
Having a soil tested for organic and nutrient content is a good idea before the addition of any amendment. The test results can indicate what nutrients are lacking in addition to how much compost or other organic material should be added. Additionally, knowing the attributes of the compost or amendment is wise. Ask the producer of the product for an analysis, or have the material tested by a soils lab. Finally, obtain advice from a horticultural expert regarding the soil types in your area and the needs of specific plants.
For amendments to effectively enhance soil properties, thorough blending or tilling is important in any area that roots will initially grow. The deeper that amendments can be blended into the soil, the better. For lawns, a minimum of six inches is recommended. For most shrubs, digging a donut-shaped ring approximately three or four times the width of the root ball which extends down an additional six inches below the bottom of the root ball is a good idea. The root ball itself should sit on an intact or well stabilized soil platform.
For most trees, the planting hole preparation is the same as for shrubs, except that minimal amending of native soils is recommended. Rather, after planting, start a program of nutritious surface mulching to slowly improve all soil within the tree’s drip line. Stake a tree on either side and loosely tie it as low as possible for support during its first year to protect and help the tree get established.
Water efficient irrigation systems are also waste efficient. By providing water in moderation, and only to where a landscape requires moisture, excessive plant and weed growth can be avoided. Recent advances in irrigation technology allow for precise delivery of water with very little waste. Drip systems and micro-emitters have become very cost effective when evaluated against water restrictions and rising water costs. The real solid waste benefit of these systems is that water and fertilizer go toward growing the plants desired, preventing nutrient-consuming and waste-generating weed growth in other areas. Always amend and blend a soil prior to installing the irrigation systems to avoid damage to the system.
- Conserves water.
- Provides lots of attractive planting options.
- Presents minimal pest and disease problems.
- Thrives with little fertilization.
- Requires low pruning and maintenance.
- Saves valuable landfill space!
All of this adds up to time and money savings for you.
Irrigation and Training Research Center
California Polytechnic State University, San Luis Obispo
Water Use Efficiency
California Department of Water Resources