Xeriscaping

In 1978, an environmental planner from the Denver Water Department’s water conservation task force coined the word “xeriscape” (zeer-eh-scape) from the Greek word xeri for dry, needing little water, and scape meaning vista or view. Xeriscaping embodies the principles of water conservation through creative and appropriate landscaping, and results in reduced maintenance times and costs.

Xeriscaping can help preserve our freshwater resources, insofar as nearly 50% of our water usage is for turf grass and landscape plantings — and all that run-off has to go somewhere.

Xeriscaping is based on eight principles that have been used separately for many years, or in different combinations in traditional landscaping practices. Not until the advent of xeriscaping have they been employed collectively:

1. Planning and Design
2. Creating Practical Turf Areas
3. Using Mulches
4. Irrigating Efficiently
5. Improving the Soil
6. Using Appropriate Plants
7. Maintaining Your Landscape and Garden Properly
8. Capturing Rain and Snow Run-Off

When implemented correctly into one holistic method, the result is a significant reduction in water consumption without loss of beauty.

1. Planning and Design

The most important step in xeriscaping is planning and design. Being thoughtful in this stage will allow the landscape to be installed in phases, and will also help in avoiding costly mistakes. The first phase in planning is defining what is wanted from the landscape and how much time is to be spent maintaining it. Here are some considerations when planning:

• Yard Activities ~ children's play areas; entertaining; outdoor games
• Storage Needs ~ tool shed; firewood; RV; Boat; additional parking
• Garden Interests ~ vegetables; rocks; perennials; home orchard;
specific plants to be included in the plan; annuals; plantings for
beneficial insects, butterflies and hummingbirds
• Style & Appearance of Planting ~ formal or informal;
monochromatic or colourful; cultivated or native

The next phase in planning is to identify important features and existing conditions in the yard, such as:

• Views ~ views that should be preserved, or unsightly features
needed to be screened
• Existing plants ~ plants that will be included in the new
scheme
• Topographic features ~ Slopes, that need terracing
(terracing slopes reduces run-off); hardscapes or low spots that
drain poorly
• Micro-climates (i.e. shade areas, hot spots) ~ Microclimates are
   defined by buildings, existing plants, and topographic
   features that alter to some degree the climatic conditions of
   the whole area; for instance, unshielded planting areas on south
   and east facing slopes will receive more sunlight exposure than
   west or north facing slopes
• Identify water-use zones ~ Very low water use zones are
   south and west facing slopes, where plants should require little,
   if any, supplemental water; low water use zones require
   supplemental water in addition to natural precipitation;
   moderate to high water-use zones should be limited in size and
   situated in high-use or high visibility areas near entryways,
   patios, and decks

Now you’re ready to design your xeriscape by drawing a simple site plan on graph paper (for scale). Be sure to make multiple copies. Include home location, existing walls, fences, trees, and shrubs. The following sections list considerations when planning a design.

2. Creating Practical Turf Areas

Lawn areas should be limited to a functional size Lawn areas have the highest water demand and should be limited to a functional size, and surrounded with a low water use zone to capture overspray. Aerating lawns twice a year will decrease run-off and increase the amount of water getting to the roots. Bluegrasses should be replaced with rye and fescue varieties that are hardier and require less water — but remain soft underfoot.

Consider replacing existing lawn areas with ground covers, mulches, or hardscape — paver stones, gravel, or stone — especially in these areas:

• Along fences
• On steep slopes where water tends to run-off
• Corners of lawns where it is difficult to water without overlapping
onto other areas
• Narrow strips of lawn between the house and a sidewalk or
driveway
• Irregularly shaped lawn areas that do not fit the normal pattern of
most sprinklers

For information on obtaining a lush, pesticide-free, and low maintenance lawn, visit the Naturally Hamilton website.

3. Using Mulches

Mulches cover and cool soils, reduce weed growth and ease their removal, minimize evaporation and exposure to wind, and provide landscape interest with colour and texture. Mulches can also capture rain and snow to allow for slower infiltration and less run-off. Here is an example list of mulches by type:

Organic Inorganic
• Straw • Pea gravel
• Wood Chips • Marble chips
• Ground Corn Cobs • Stone
• Compost
• Bark nuggets
• Newspapers

Use coarse compost that is easily dug into soil for new plantings in areas of high planting activity, like flowerbeds. For permanent plantings like trees and perennials, use bark chips that will release nutrients slowly. Excessive mulch can be more harmful than none at all, so for annuals and perennials use 3-5 cm (1-2 inches) and for trees and shrubs use 5-8 cm (2-3 inches).

Never use black plastic sheeting under mulch, as it prevents air and water exchange — use newspaper instead. Landscape fabric is unnecessary under organic mulches because the mulch decomposes, forms a layer of soil on top of the fabric, and renders the fabric useless.

4. Irrigating Efficiently

Irrigation systems can be easily designed to provide different amounts of water to various water demand zones (low, very low, moderate to high) for maximum efficiency. Use sprinklers to water lawns, and for trees, flowerbeds, and groundcovers use low-volume sprinklers, or drip- or bubbler-emitters. Annual maintenance is very important, as eliminating the unnecessary waste of leaks can lead to 30-80% in water savings.

Water deeply and less frequently instead of shallow daily watering. If you use a hose, apply water in areas of need like grass that has begun to turn gray-green in colour. For shrubs and perennials, water to a depth of one foot, for annuals and vegetables water 6-8 inches, and for trees water very deeply. To check how thoroughly you have watered you will need a round mouth shovel. Excavate the earth or garden soil to a depth equal to your shovel blade (approximately 8 inches or 20 cm). Then, gently apply pressure to the shovel handle away from you until you can see into the soil below; you should now be able to see the depth at which you watered. If not, use your fingers to feel how deep you've watered. Gently pull the shovel out of the soil and lightly pack the soil where you dug. This should not cause damage to your grass or garden and is actually a good way of aerating your soil! If the depth is greater than your shovel depth, then you have watered thoroughly for shrubs and perennials. Lastly, provide less water to shaded areas and north- and west-facing slopes, and apply water to slopes more gradually than on flat areas. Aerating your lawn twice a year will help increase infiltration.

5. Improving the Soil

A good soil is an equal mix of sand, peat, and compost. The key to a good landscape is to test the native soil and determine the correct amendments and amounts needed. Soil improvement can provide better infiltration, proper aeration, and improved water-holding capacity. Compacted soils, usually clay, result in quick puddling and excessive run-off and should be aerated in the spring and fall. Soils with good drainage — sandy soils, for example — lose water and nutrients due to poor water retention and leaching.

A good soil is an equal mix of the following:

• Sand or other fine aggregate (vermiculite) to improve drainage
and increase the oxygen available to plants
• Peat for nutrients and water retention
• Compost for nutrients and increased water holding capacity

6. Using Appropriate Plants

Native plants are a great choice! Water efficient plants that are compatible with soil, exposure and irrigation system conditions should be used in a xeriscape plan. Native plants are a good choice because they are adapted to local precipitation norms, require less pesticides (as they are pest tolerant), and less water (drought tolerant). The Hamilton Coalition on Pesticide Issues has some great information on native plant species.

7. Maintaining Your Landscape and Garden Properly

Fertilize you lawn in autumn. Regular pruning and weeding, proper fertilization, pest control, and water schedule adjustments are all important maintenance considerations. Annual maintenance of the irrigation system will ensure accurate water delivery to planted areas and prevent water wastage. Healthy plants are more able to resist pest and disease problems so keep your plants healthy — prune any diseased plant material throughout the year to prevent pest infestations. Don’t forget that weeds need water too, so removing them regularly will decrease your water use.

Use organic or organic-based fertilizers to help increase the humus content of soil and improve water-holding capacity. Remember that compost is an excellent fertilizer for your gardens and, when sieved, is great for your lawns too (click here for composting information). Feed lawns in the autumn, not in late spring-early summer, to avoid dramatic growth periods that require more water and result in shallow root growth.

If you would like to know more about safe pesticide alternatives for pest and disease control, click here.

8. Capturing Rain & Snow Run-Off

Keep stormwater out of the sewer through retention, infiltration, and diversion.

An average sized home in Hamilton can keep up to 100,000 litres of water out of the sewer every year by practicing the following techniques:

• Retention
• Infiltration
• Diversion

Retention
Plan to harvest water run-off from downspouts, outbuildings and paved surfaces (driveways, sidewalks, patios, etc.), and channel water back onto the landscape to a retention pond or to water loving trees like aspen, birch, or cedar. Get creative in the ways you can retain water on your property. Here are some ideas:

• Use rain barrels to capture rainwater from downspouts
(click here to see models available at Green Venture)
• Build a rain garden to hold and treat run-off; rain gardens are also great for attracting birds and butterflies

Infiltration
Eliminate non-porous surfaces like driveways, pathways, and sidewalks. Also:

• Change pathways to clover, dirt, loose gravel, or well-spaced
stones
• Use porous pavements (pre-cast blocks) to allow water to
infiltrate into the ground
• Limit paved driveway surfaces to just the area where the tires
roll and fill the area between with dirt, gravel, grass, or other
groundcover

Diversion
Redirect your downspouts so that stormwater runs onto porous, absorbent ground where it can infiltrate (soak into ground) and be naturally cleaned before it is re-introduced into a water body. Aerate your lawn at least once during late fall (preferably a second time in the spring as well) to increase infiltration rates on turfed areas.

Here is a list of other techniques you can practice to reduce run-off contamination and protect local watersheds:

• Follow the stoop-and-scoop method for pet waste (CLICK HERE
for more on pet waste composting)
• Check automobiles for leaks, and fix them
• Keep automobiles off the road, use bicycles or the bus instead
• Reduce or eliminate pesticide and fertilizer use (click here
to visit Naturally Hamilton and find out how!)
• Leave grass clippings on the lawn to reduce fertilizer applications
and increase water holding capacity
• Don’t put anything down the storm sewer, except rain and snow
• If you have to buy hazardous household products, buy only the
amount you need and use it up wisely (share with a neighbour,
or local community organization) and dispose of it safely
• Wash vehicles over soft surfaces (where run-off can penetrate)
or at a car wash
• Use a broom to clean your driveway and walkway
• Incorporate a green roof (roof garden) into the building to
intercept and retain rainwater and decrease run-off

Xeriscaping isn't zeroscaping! A good design will enhance the beauty of your surroundings, improve the comfort of your home with windbreaks and shade, create habitat for songbirds and other beautiful wildlife, and use less water.

Sources:
Xeriscape Colorado
Peterborough Green-Up
The Ontario Clean Water Agency

Sources:
Xeriscape Colorado - a program of the Colorado Wise Water Council, promoting creative approaches to water-conserving landscapes
Peterborough Green-Up - provides education, services, and resources to enable citizens to take up environmentally healthy lifestyles
The Ontario Clean Water Agency ~ Water Efficient Landscaping (.pdf 337 KB) - an informative guide put out by the Ontario Clean Water Agency covering the many aspects of water efficient landscaping

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