What is Xeriscape
The term Xeriscape was created by Nancy Leavitt in conjunction with the Denver Water Department in 1981. The goal then and now is to develop sensible gardening methods which ensure water conservation. The word, Xeriscape, comes from the Greek word “xeros”, meaning dry. This in combination with the word, landscape, gives us Xeriscape. Xeriscape is very beneficial to the environment in the arid west helping both nature and man.
The word Xeriscape is pronounced like zeer-i-scape. Unfortunately early and misguided attempts at water conservation incorporated too much “rock mulch”.
Those early efforts represented “zeroscapes”. Xeriscapes are entirely different.
Today, many people cannot tell a Xeriscape garden from a more traditional planting without close inspection. There are seven commonsense steps to water wise gardening that can be applied to new spaces or to retrofit old gardens.
Seven Steps to Xeriscape
Planning and Design
Good planning and design may seem obvious but it is the key to final success. With proper advance planning and a drawn design, the other six Xeriscape steps will be easier to accomplish.
Each area around a dwelling or other structure exists in or creates its own microclimate. The existing location of outside water sources may pose a distance problem and possibly limit the finished design. Drawing a sketch of the site will demonstrate some of these differences. The location for plantings is critical to their successful growth and survival. If done to scale, the drawing will also allow basic calculations for the size and quantity of items needed for the new Xeriscape garden.
The north and east sides of a building will receive less sunlight, therefore, the soil will be cooler and probably hold more moisture throughout the year. South and west exposures will be warmer and drier.
Prevailing winds will affect the garden site as will shade from nearby large trees. By mapping the total site in the planning stage, these unique aspects or microclimates will be seen and can be studied for the best Xeriscape treatments.
Ultimately, plants requiring more moisture or cooler environments will be grown together and those with very low water needs that can tolerate full sun will be grouped together. Plants with similar needs should be grouped together in the best location possible. Also, considerations for plant heights, colors, and blooming periods are best selected based on location.
Lawn and/or turf areas should be planned according to use. Will the grass be used for a play area or for beautification or as a buffer between residences or other view distractions?
Another thing to consider is slope. Sloping areas can be very difficult to mow and will function better if terraced and planted to perennial ground covers.
Advance total planning ensures saving time and money. Key planning concerns include the following: water source, slope, use, space requirements based on microclimates, width and height of plantings, uniformity of water requirements, color and blooming periods.
Soil Improvement
Most Colorado soils are predominately sand and clay minerals. In their natural state, these soils usually contain little organic matter or humus. Sandy soils do not hold much water or many nutrients for plants. Clay soils become hard and compacted making it difficult for water, air, and plant roots to penetrate. For lawns and gardens to thrive, the natural soil needs to be amended with organic matter like aged manure or compost.
Amending the soil is the most important step when the actual physical work begins on the Xeriscape garden. There are many local companies providing aged manure or well composted wood chip and manure products. Composting organic matter creates weed-free humus and gives the finished soil product a light texture. Improving the soil quality allows plants to receive water, air, and nutrients more readily.
Limit Turf Areas
The greatest use of outdoor watering is concentrated on lawns. The best way to reduce this use and conserve water is by limiting lawn areas or by planning them for specific use. Limiting the size of lawns also results in time and money savings. Lawns require regular maintenance and often rely heavily on expensive fertilizer and pesticide applications.
Most Colorado lawns are planted to Kentucky blue grass. By determining the actual use for the lawn area in advance, fewer high maintenance areas can be established. In general, when used correctly, grasses offer some of the most versatile Xeriscape plantings.
There are many species available that require much less water than blue or rye grasses. Children’s play areas that require tough turf can be established to sod turf-type tall fescue, or native buffalo or grama grass.
Tall fescue is drought tolerant and when kept mowed still provides that “bare foot grass” feeling. A planting of smooth brome and tall fescue can be used as a weed free low maintenance barrier or screen if left to grow naturally. Many individual bunch grasses provide excellent color and contrast within flowerbeds.
Use Plants With Low Water Requirements
There are long lists of plants that have proven records for Xeriscape gardening. The problem with plant selection is not finding enough correct plants but actually limiting choices based on space and budget considerations.
Again, the basic plan will become the guide for plant selection by location, height, color, and blooming season. Most people collect ideas from existing gardens for their final plan. Visiting established Xeriscape demonstration gardens in the Front Range area is an excellent way to make choices. Many water departments have promoted Xeriscape gardens at their facilities and location lists are available. Most plantings in these gardens have identification tags on plants to help visitors recognize species.
Use Mulch
After improving the soil and making proper plant selections, mulch is the next most important step in the establishment of a well functioning garden.
Mulches accomplish several things in a Xeriscape planting. Mulches provide temporary cover until plants mature and “fill in” open spaces. Also, acting like a blanket over the soil, mulch reduces water evaporation from the soil surface. Because the mulch blocks sunlight, it prevents weed growth but still allows air and water circulation.
Technically, almost anything can be used as mulch. Straw, newspapers and rocks have all been utilized as mulch. A popular method for applying mulch today incorporates the use of landscape fabric. (This is not black plastic.) Landscape fabric looks and feels much like felt. This fabric is placed directly over the soil and then topped with shredded bark, wood chips, small rocks or other aesthetically pleasing material. Landscape fabric “breathes”, allowing air and water to circulate.
Effective Irrigation
Once the garden and lawn is planted, most maintenance time, energy, and money will be spent on watering. Most, but not all, irrigation can be reduced with the initial selection of drought tolerant plants and grasses and by clumping plants with greater or less water needs. Create watering zones by plant needs and location.
Over watering carries yard chemicals like fertilizers and pesticides into street gutters and is becoming a significant cause of water pollution. Drip irrigation systems help avoid this, since the emitters can place water right at the root zone. These systems are excellent for shrubs and trees. Buried porous hose and/or short umbrella or bubble sprinklers place large droplets near plants and do not lose water through evaporation as badly as fine spray sprinklers. Most garden and nursery centers have a wide choice of water conserving systems. Many area Soil Conservation Districts also sell drip irrigation supplies.
Appropriate Maintenance
As with so many long-term projects, the yard and garden around residences require regular upkeep. Weeding, watering, mowing, pruning, fertilizing and pest control will still be necessary in the Xeriscape setting.
In summary: weeding, watering and mowing can best be controlled by limiting turf grass area, mulching and selection of lower growing turf grasses. Pruning labor is relative to the numbers and types of woody shrubs or trees planted.
Insect pests or plant diseases should pose fewer problems in the Xeriscape garden. By selecting hardy, native species, part of the general disease and pest problem will be eliminated. Another way to help control pests is to allow adequate space between plants for air circulation and penetration of sunlight.
Sometimes the best intentions and planning still fail to keep disease or pests out of the garden and lawn. For those wishing to avoid the use of manmade chemicals there are many natural alternatives available at garden centers or through publications for gardeners.