Water-Wise Plants Installation Tips

Planting Xeriscape is much like planting any trees, flowers, shrubs. The first task is soil preparation and grading, then planting, fertilizing and mulching. Keep in mind the seven principles of Xeriscape when planning your landscape:

  1. Planning and design
  2. Soil improvements
  3. Efficient irrigation
  4. Zoning of plants
  5. Mulches
  6. Turf alternatives
  7. Appropriate maintenance

Following these principles will help ensure the success of your water-wise landscape.

Soil Preparation

Prepare the ground with these goals in mind:

  • Good drainage
  • Smooth contours for even growth
  • Rainwater detention for thirsty plants
  • Good topsoil

You should slope the ground away from buildings and grade to one inch below driveway or sidewalk level. When possible use mulch or gravel borders to avoid turf areas that are difficult to irrigate efficiently.

About Topsoil
Well drained fertile loam is the ideal soil for most plants. Some native plants may actually prefer poorer quality soil. Check with your local nursery for information on your specific plant choices. Sandy or gravelly soils tend to dry out too quickly. Heavy clays are hard to work, and may become water logged and compacted. If your soil is unsuitable, you may need to buy good topsoil, but most topsoil is useable. Heavy topsoil can be improved by adding sand or organic matter, or both. clay or silt and organic matter can be added if the topsoil is too light.

Improve Your Topsoil
Available organic matter can be used to enhance the quality of your topsoil. There are several sources of organic matter. The one to use depends upon local availability and cost. Commonly recommended soil additives include:

  • Mushroom manure, well rotted
  • Chicken manure with sawdust (should be composted)
  • Peat moss
  • Peat and sand mixture
  • Any readily available compost

Roto-till the soil to a depth of 4 to 6 inches. Finish grading:

Zoning of Plants

Different areas in your yard get 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 in your yard which matches these requirements. A good rule of thumb is to put high water-use plantings in low lying drainage areas, near downspouts, or in the shade of other plants. It’s also helpful to put higher water-use plants where it is easy to water.

Dry, sunny areas or areas far from a hose are great places for the many low water-use plants. Planting a variety of plants with different heights, color and textures creates interest and beauty.

By grouping your plants appropriately, you minimize water waste while ensuring that your plants will flourish in the right environment.

Planting

Here are some general instructions for planting. Always check for specific instructions related to your individual plant selections. Obviously a saguaro cactus will require different planting techniques than a tea rose.

Digging
The planting hole should be dug approximately twice as wide as the soil ball. Measure the height of the root ball and dig the hole one-two inches less deep. Do not dig deeper or the plant will be too deep once the disturbed soil settles. A tape measure or a simple length of twine or string can be used to measure the root ball before digging.

When digging is complete, roughen up the sides of the hole. This will help the plant to root in more easily.

Planting the plant
If the plant is in a container of any kind, remove it at the planting site and place the plant in the hole. Do not plant too deep!

Once it is in the hole, hold it erect and make sure it is centered and straight from all sides. Bare root plants (usually trees) should be placed with the largest branches facing the prevailing winds and with the roots straightened and spread evenly within the hole.

Once your plant is properly placed, you can begin to backfill using the original soil dug from the hole. While poor soils may benefit from the addition of organic soil amendments such as peat moss or other composted products, you should never completely backfill with an amendment. If a soil amendment is called for, it should be mixed thoroughly with the original soil prior to backfilling the planting hole. In most cases, plants will grow best if the original soil is altered as little as possible. If roots suddenly encounter a completely different type of soil, they will have difficulty growing through this "wall" and into the surrounding soil. This has much the same effect as if you had not removed the container and will prevent proper root growth and drainage. Instead, create a transition zone so that the change from the amended soil to the original soil is minor.

A qualified nursery professional can advise you on whether or not amendments are appropriate for your conditions. Remember that too much amendment or an inappropriate amendment will only make soil problems worse.

Plants may benefit from being fertilized at the time of planting. A slow-release, complete fertilizer that is high in phosphorus (the middle number) will aid in the development of a strong and healthy root system. Once again, the fertilizer should be mixed thoroughly with your original soil prior to backfilling. Never put fertilizer directly on the roots of your plant and always use it in accordance with label directions.

As you fill the hole, backfill evenly around the plant to keep air pockets to a minimum. If planting bare root, the plant can be lifted up and down slightly as you fill to help soil settle in around the roots.

Once your planting hole is approximately 3/4 full of backfill, water the plant in thoroughly to further eliminate air pockets in the backfill. Then complete filling the hole and water in thoroughly once again.

Care after Planting

Irrigation and watering
It is very important for your new plantings to be watered regularly. However, the type of soil and the weather conditions should determine how frequently and how much you water.

Never water automatically without first checking the soil to determine if watering is needed. Even low-water-use plants will need water to become properly established. Sandy soils generally will need to be watered more frequently than clay soils, but always check before automatically watering the plant.

Since roots grow where oxygen and water are most available, short and frequent waterings will result in the development of a shallow root system. Watering deeply, thoroughly and only as needed will encourage a deep and healthy root system that will be able to withstand environmental stresses.

Heavy watering of lawns next to newly planted trees and shrubs can be detrimental to those trees and shrubs.

Mulching
Mulching is a great addition to your garden and landscape. Mulch helps keep plants roots cool, prevents soil from crusting, minimizes evaporation, and reduces weed growth. Mulches also give beds a finished look and increase the visual appeal of your garden. Organic mulches, such as bark chips, pole peelings or wood grindings, should be applied at least 4 inches deep. Because they decompose over time, they’re an excellent choice for new beds. As plants mature and spread, they’ll cover the mulched areas.

Inorganic mulches include rocks and gravel, and should be applied at least 2 inches deep. They rarely need replacement and are good in windy spots. However, they should not be placed next to the house on the sunny south or west sides, because they tend to retain and radiate heat. Mulch may be applied directly to the soil surface or placed over a landscape fabric. (Note: Do not use black plastic because it prevents air and water from reaching to the plant roots.)

For information on planting a Blue Gramma lawn:
www.highcountrygardens.com

Sources:
www.forestlakefloral.com
www.water.denver.co.gov

Xeriscape bibliography:
www.xeriscape.org