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It's a remarkable
moment in the history of landscaping. People are beginning
to look at the impact of their gardens and are realizing that
they can have a beautiful landscape without making excessive
demands on the environment. You might call it the "Post-Xeriscape
Era," since we've come to understand that there's more
to having a low-impact landscape than just saving water.
Today, we look
at the things that flow into and out of a landscape and try
to minimize their use. For example, a typical garden requires
a number of resources for its construction - concrete, lumber,
plants, compost, PVC irrigation pipe and so forth. There will
be additional inputs needed for the maintenance of the garden,
such as water, fertilizer, fuel to operate power equipment,
pesticides and herbicides, to name a few. A garden also generates
materials that may be harmful to the environment, such as
lawn clippings, tree and shrub prunings (collectively referred
to as "greenwaste"), polluted runoff of chemical-laden
water and others. The idea behind sustainable landscaping
is to develop ways to reduce these inputs and outputs without
sacrificing beauty, economy and ease of maintenance.
As you'll see
in this article, a sustainable landscape can actually be less
costly and easier to maintain, because it's designed correctly.
Far from being a sacrifice, developing a sustainable landscape
can bring you rich rewards and beauty you may not have thought
was possible. Enjoy this brief introduction to sustainable
landscaping and please call if you have any questions.
MATERIALS
When selecting
materials for the construction of your landscaping, first
consider re-using things such as railroad ties, broken concrete
for walls and other cast-offs. Use your imagination and remember
that rustic materials often look great in an outdoor environment.
Next, think about
recycled products. One of the interesting new materials available
is plastic "lumber" made from recycled milk and
soda bottles; it's attractive and durable and comes in a number
of colors.
Where you must
use new materials, make renewable resources your first choice.
Even natural materials can be a problem. For instance, decomposed
granite is strip-mined from natural or formerly natural areas.
Remember too that even renewable materials come from somewhere
- using redwood lumber means trees had to be cut down.
Reduce the use
of decks made from redwood, high-tech patio furniture and
other consumptive goods.
Always ask yourself,
"Where did this come from?" If you don't know the
source of something, ask questions.
Whatever you use,
be sure it will be durable. Build to last. It's better to
use more materials doing something right than to cut corners
and have to re-do your work in a few years.
WATER
Select from among
the hundreds of varieties of attractive water-efficient plants,
many of which have become available only in the past few years.
Use native species whenever possible, or plants from other
Mediterranean climates.
Plant less densely
- don't try to fill up every square inch with plants. This
will balance the biomass - the quantity of water-using vegetation
- with the available rainfall. Reduce lawn areas to just what
you'll actually use. One thousand square feet of lawn or less
is adequate for most families. Beware of claims about "drought-tolerant"
or "low water-use" lawn grasses - there's no such
thing. Hybrid bermuda grass is the lowest water-use turfgrass
variety on the market, but it still needs quite a bit of water,
compared to water-efficient landscaping. Considerturf a luxury
best used in moderation.
When you plant,
incorporate organic material into your soil to improve its
water-holding capacity. Your own compost is best, but there's
rarely enough to go around. Buy the best quality compost and
make sure it's nitrolized to prevent damage to your new plants.
Avoid wood shavings, sawdust, fresh manures or mushroom compost.
After planting,
be sure to apply a mulch on top of the soil. You can use bark,
crushed rock or other attractive materials. Mulch helps keep
the soil from drying out, discourages water-stealing weeds,
hides drip tubing, keeps the dust down in summer, provides
a safe walking surface and looks better than bare ground.
'Be sure your
irrigation system is efficient - design your lawn sprinklers
so they don't apply water faster than your soil can soak it
up. Place sprinkler heads so they will water only the lawn,
with a minimum of overspray. Use drip for everything but lawn
areas. Avoid planting sheets of herbaceous ground cover that
must be sprinkled; use individual plants and a drip system
instead. Drip systems use a tiny fraction of the water that
sprinklers do.
Use a controller
for the lawns - it can be cycled to prevent runoff and save
you the trouble of turning valves on and off all the time.
For the drip system, think about whether you want a controller
or not. Most controllers make you water every week or two
and that's too much for many drought-tolerant plantings. There
are valves available that can be set manually and will shut
off after delivering a set amount of water - this is often
a better approach for drip.
To conserve rainfall,
use permeable paving or slope paved areas towards planted
areas. Consider grading to allow rainwater to pond and soak
in (make sure this won't cause erosion problems).
Finally, don't
overwater. Check soil moisture before irrigating and apply
only what the plants actually need.
CHEMICALS
Choose plants that
don't require a lot of fertilizer to keep them healthy, and
that are naturally resistant to pests and diseases. This will
reduce the need to feed and spray. When you do feed, use organic
fertilizers or, even better, compost produced from your own
trimmings. Use safe pesticides or biological control methods
such as beneficial insects that prey on pests.
OTHERS
Fossil fuels are
used to deliver materials to the site, to transport workers
(including gardeners) to and from the job, to operate power
equipment such as mowers and chainsaws and to haul away refuse.
A less obvious use of fossil fuels is in the production of
fertilizer and many garden chemicals. Sustainable landscaping
reduces these demands.
Landscaping can
also reduce energy use inside the home. Properly located shade
trees can provide climate control, reducing heating and cooling
costs. Trees and shrubs used as windbreaks can also moderate
the microclimate in and around the home.
Landscaping can
provide or enhance habitat for wildlife by supplying food,
shelter and nesting materials. (Remember to preserve natural
areas whenever possible.)
Finally, landscaping
can mitigate fire hazards by providing greenbelts of low-fuel
vegetation around homes.
IN
CONCLUSION
Sustainable landscaping
is based on common sense and good design. It's about stability
- creating something that works because it's in harmony with
the local environment and has an internal system of checks
and balances. It's not perfect - you'll still need to use
resources, but in a much more sensible way. Done right, landscaping
can be a part of the solution, not part of the problem.
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