Photo by/from Jeffrey Beall

Xeriscaping is the process of landscaping or gardening that reduces or eliminates the need for supplemental water from irrigation. It is promoted in regions that do not have accessible, plentiful, or reliable supplies of fresh water and is gaining acceptance in other regions as access to irrigation water is becoming limited. Xeriscaping may be an alternative to various types of traditional gardening.

In some areas, terms as water-conserving landscapes, drought-tolerant landscaping, and smart scaping are used instead. Plants whose natural requirements are appropriate to the local climate are emphasized and care is taken to avoid losing water to evaporation and run-off. The specific plants used in xeriscaping depend upon the climate. Xeriscaping is different from natural landscaping, because the emphasis in xeriscaping is on selection of plants for water conservation, not necessarily selecting native plants.

Photo by/from Potomacpalms

Public perception of xeriscaping has frequently been negative as many assume that these types of landscapes are ugly expanses of cactus and gravel. However, studies have shown that education in water conservation practices in the landscape can greatly improve the public’s perception of xeriscaping.

Denver Water coined the term xeriscape in 1981 by combining “landscape” with the Greek prefix xero-, from kiros (xeros), meaning dry. The term zero-scaping or zeroscaping is sometimes substituted for xeriscaping due to phonetic similarity. When used seriously, zero-scaping usually refers to a different type of low-water landscaping that is often devoid, or nearly devoid of plants. Because o is the most common connecting vowel in Greco-Roman vocabulary, xeriscaping is sometimes misspelled as xeroscaping.

Some homeowners associations have strict rules requiring a certain percentage of land to be used as lawns but these rules either have been or are in the process of being overturned in many areas.

Photo by/from Michael Barera

Originally conceived by Denver Water, the seven design principles of xeriscaping have since expanded into simple and applicable concepts to creating landscapes that use less water. The principles are appropriate for multiple regions and can serve as a guide to creating a water conserving landscape that is regionally appropriate and since they were conceived for homeowners they are easy to implement.

1. Plan and design: Create a diagram, drawn to scale, that shows the major elements of the landscape, including house, driveway, sidewalk, deck or patio, existing trees and other elements.

Once a base plan of an existing site has been determined, the creation of a conceptual plan (bubble diagram) that shows the areas for turf, perennial beds, views, screens, slopes, etc. is undertaken. Once finished, the development of a planting plan that reinforces the areas in the appropriate scale is done.

2. Soil amendment  – Most plants will benefit from the use of compost, which will help the soil retain water. Some desert plants prefer gravel soils instead of well-amended soils. Plants should either fit the soil or soil should be amended to fit the plants.

3. Efficient irrigation: Xeriscape can be irrigated efficiently by hand or with an automatic sprinkler system. Zone turf areas separately from other plants and use the irrigation method that waters the plants in each area most efficiently. For grass, use gear-driven rotors or rotary spray nozzles that have larger droplets and low angles to avoid wind drift. Spray, drip line or bubbler emitters are most efficient for watering trees, shrubs, flowers and groundcovers.

If watering by hand, avoid oscillating sprinklers and other sprinklers that throw water high in the air or release a fine mist. The most efficient sprinklers release big drops close to the ground.

Water deeply and infrequently to develop deep roots. To reduce water lost to evaporation, never water during the day. With the use of automatic sprinkling systems, adjust the controller monthly to accommodate weather conditions. Also, install a rain sensor to shut off the device when it rains.

4. Appropriate plant and zone selection: Different areas in a yard receive different amounts of light, wind and moisture. To minimize water waste, group together plants with similar light and water requirements and place them in an area that matches these requirements. Put moderate-water-use plants in low-lying drainage areas, near downspouts, or in the shade of other plants. Turf typically requires the most water and shrub/perennial beds will require approximately half the amount of water.
Dry, sunny areas support low-water-use plants that grow well in the specific climate. Planting a variety of plants with different heights, color and textures creates interest and beauty.

5. Mulch: Mulch keeps plant roots cool, prevents soil from crusting, minimizes evaporation and reduces weed growth. Organic mulches, such as bark chips, pole peelings or wood grindings, should be applied 2 to 4 inches deep. Fiber mulches create a web that is more resistant to wind and rain washout. Inorganic mulches, such as rocks and gravel, should be applied 2 to 3 inches deep. Surrounding plants with rock makes the area hotter; limit this practice.

6. Limited turf areas: Native grasses (warm-season) that have been cultivated for turf lawns, such as buffalo grass and blue grama, can survive with a quarter of the water that bluegrass varieties need. Warm-season grasses are greenest in June through September and may go dormant during colder months.

Native grasses (cool season) such as bluegrass and tall fescue, are greenest in the spring and fall and go dormant in the high heat of the summer. New cultivars of bluegrass, such as Reveille, and tall fescue, can reduce typical bluegrass water requirements by at least 30 percent. Fine fescues can provide substantial water savings and are best used in areas that receive low traffic or are in shady locations.

Use the appropriate grass and limit the amount of grass to reduce the watering and maintenance requirements.

7. Maintenance: All landscapes require some degree of care during the year. Turf requires spring and fall aeration along with regular fertilization every 6 to 8 weeks. It should be cut to a height of 3 inches, allowing the clippings to fall. Trees, shrubs and perennials will need occasional pruning to remove dead stems, promote blooming or control height and spread. Much of the removed plant material can be shredded and used in composting piles.

One of the major challenges to the public acceptance of xeriscaping is the cultural attachment to turf grass lawns. Originally implemented in England, lawns have become in some regions a symbol of prosperity, order and community. In the United States turf grasses are so common that it is the single most irrigated crop by surface area, covering nearly 128,000 square kilometres (49,000 sq mi). Despite the high water, fertiliser and maintenance costs associated with lawns, they have become the social norm in most urban and suburban areas, even if they are rarely used for recreational purposes or otherwise. Xeriscaped landscapes offer an alternative to the over use of turf grass lawns but are not widely accepted because of preconceived notions of what it means to xeriscape. Xeriscaping can include lawn areas but seeks to reduce them to areas that will actually be used, rather than using them as a default landscaping plan.