Xeros. No, this is not the name of our latest comic book. It is the Greek word for dry. Phyte is Latin for plant, and botanists have put the Greek and Latin together to produce "Xerophytes," which are plants specially adapted to survive in dry environments. The Mojave Desert is a xerophytic environment and the plants that grow there are xerophytes (examples: cholla cactus, Palo Verde tree, desert willow, mesquite chilensis, jojoba, sage and germander). Gardeners have adopted xeros as a prefix, and the stuck it on the last half of the word landscaping to come up with "xeriscaping."
Hydro-zoning is the practice of grouping together plants with similar water requirements in order to conserve water. When our goal is to conserve water but still maintain an attractive landscape, both xeriscaping and hydro-zoning will become part of our overall design.
There are no plants which can survive without water! Xerophytes can survive with less water than other plants because they have special modifications such as small leaves, thick, waxy leaf coatings, spongy water storage cells and/or reduced metabolism. Even though a plant is labeled as drought tolerant, it will require the same care and attention as a conventional plant for the first year or two after its installation. After the second or third year, the drought tolerant plants will survive on less water than the average plant. As you replace water-dependent plants with xerophytes, you will eventually reduce water usage.
Lawns are probably the heaviest users of water in the home landscape. If you reduce the amount of lawn area and replace it with gravel, tanbark or rock fines, you will reduce--by a significant amount--the water used for irrigation.
In addition to reducing water usage, our goal is to produce an attractive landscape. If you are willing to devote a small extra portion of your water allowance to hydro-zoning some mesophytes (meso=middle), you can have a very attractive landscape. As you plan your design, remember Mr. Ed's Rule Number 14: Trees and turf don't mix!
The hottest, driest part of the garden will be the most exposed section; this is next to sidewalks, driveways and other open areas. This will be the area for your xerophytic planting. Prepare the soil in our recommended fashion (see our
Soil , Its Care and Improvement Care Guide) throughout the entire area before doing any planting. There is no special soil for the xerophytes. For a tree in your xerophytic section, either mesquite or Palo Verde--with its mass of yellow spring flowers--will work. Bush germander, silk-tassel, rockrose, carpentaria, and lemonade berry are a few of the shrubs suitable for the xerophytic area. Long blooming plants are not common in xerophytic areas but a few choices are
Aloe brevifolia,
Aloe saponaria, artemisia, butterfly weed, chuparosa, spring starflower (bulb), lapeirousia (bulb), perennial sweet peas, and Queen Anne's lace. Most of these perennial flowering plants will survive on only winter rain. Plant shrubs and perennials in groups of the same kind, not by themselves, so they appear as they appear in nature.
For accents in the xeriscape, place boulders buried one-third to one-half their depth into the ground. Nothing looks more foolish than to place boulders on the surface of
the ground, where they are referred to as cemetery stones. A few low growing grasses such as Stipa and Deschampsis planted around the boulders will enhance the natural feel of the design. For an extra bit of drought resistant color, some small lewisia next to the grasses will catch the spectator's eye. This xeriscape should be mulched with crushed rock such as 'Desert Gold' over a weed barrier.
A small piece of lawn (bluegrass, perennial ryegrass mix) would be permitted interior of the xeriscape. The two areas should be separated by deep curving bender board. Within the curves of the bender board and surrounding the lawn should be planted, low water requiring colorful perennials such as salvia, penstemon, lavender, gaura, Douglas iris and crane's-bill geranium. If you need another big, showy plant; 'Royal Purple' smoke tree is an excellent addition. All of these plants will need more water than the xeriscape but after the first few months, the lawn and the perennials will flourish on the same watering schedule.
The xeriscape plants and perennials should have one annual Valentine's Day treatment with an all-purpose fertilizer such as Formula 49.
All of the plants may need special care during the first year, but after that the automatic watering system should suffice. The xeriscape plants must be on their own watering schedule with drippers being most efficient and most economical. The tree, if used, must also have its own watering system. If properly adjusted, "pop-up" sprinklers can irrigate both the lawn and the perennial flower beds within the lawn curves. They too must be on a separate schedule. By selecting the proper plants, you will have created a xeriscape as part of the overall hydro-zone plan.
Hydro-zoning and xeriscaping will achieve the following goals:
• Conserve water
• Provide attractive planting options
• Reduce pest and disease problems
• Reduce fertilizer use
• Reduce pruning and maintenance
The perennial area and any other non-lawn and non-xeriscape areas must be mulched with 2 to 4 inches of organic mulch such as Forest Blend, Redwood compost, Fir bark, Gold Rush or Bumper Crop. These products will permit water and fertilizer to pass through to the plants. Avoid Gorilla Hair, which has low water permeability.
Your carefully planned water-conserving landscape will be as handsome as any typical landscape and will use only a fraction of the water typically required. The landscape will require fewer hours of your time for maintenance and will save money by reducing water bills, as well as fertilizer and pesticide use.