University of Vermont Extension
Department of Plant and Soil Science
Summer News
Article
TOWARD A
"GREENER" LAWN
Dr. Leonard Perry, Extension
Professor
University of Vermont
If you have a lawn you undoubtedly want it to be green in color.
Here
are a few tips to make a lush, green lawn "green" ecologically as well,
adapted in part from NOFA Notes by Wendy Sue Harper, Ph.D
(www.nofavt.org).
Why think "green"? Much of
the chemicals you put onto lawns, whether fertilizers or pesticides,
synthetic
or organic, wash into surface water and lakes.
Most lawns don't need phosphorus, yet it is still added by many, ending
up causing algae in ponds and lakes.
This can be a huge amount, considering there are three times as much
lawn area in our country as corn. Lawns
in the U.S., both
residential and public spaces, are estimated to cover over five times
the size
of Vermont. A few environmentally sound lawn care
practices will help you prevent such contamination, save money, and
save labor.
Add fertilizer according to soil
tests, so you apply only what is needed.
Test kits are available at Extension service offices and many garden
stores. A thin layer of compost, only
one quarter inch thick, will improve many aspects of lawns and the
soil. Make sure and brush any compost or fertilizer
on impermeable surfaces (such as walks), back onto the lawn.
Leave mowing clippings on
lawns. Mowing regularly, and with a
mulching mower, will make these clippings barely noticeable.
You'll save both time and fuel in collecting
clippings, plus you'll save
money in fertilizer. Grass clippings
contain about 50 percent of nitrogen lawns
need, about two
pounds per 100 square feet. If you mow
with a rotary mower, make sure clippings are blown back onto the lawn,
as they
contain phosphorus too that you don't want washing into waterways.
Related to leaving grass clippings
is mowing at the proper height, and as needed.
Mowing high (about three inches) helps the grass shade out weeds, keeps
soils cool and moist, and this in turn encourages healthy root
growth. Mow no more than one-third of the grass
blades at a time in order to reduce stress on your lawn. I like
to not set my mower on the highest
setting, in case the lawn gets too high.
I can then mow it higher, and in a couple days mow it back a bit lower
or normal. Make sure when buying a mower
that you can set it at these high levels.
Keeping a sharp mower blade reduces
injury, and so stress and disease, on your lawn. A sharp mower
blade also can increase mower
efficiency and life, and decrease gas consumption as much as 22
percent. Sharpening blades at least once a month is
recommended by professionals.
Adding seeds to your lawn, or
"overseeding", is good once a year to replace the grass plants that
die out naturally. A thick, dense lawn
better resists weeds. If you are
overseeding, a diversity of grasses will be more adaptable to soil and
climate
changes and extremes. April or late
summer are good times to overseed.
Water properly. The usual recommendation is at least one-inch
of water per week, either from rain or irrigation. If you
need to irrigate, do so deeply, once
a week, and early in the morning if possible.
Watering late in the day keeps grasses wet at night, and makes them
more
susceptible to diseases. Light watering
more often will encourage roots near the surface that die with drought
and
stress. Topdressing your lawn with
compost each year will improve the soil water-holding capacity.
A lawn of diverse species will be
healthy, more resistant to pests and diseases and weeds,
and will stay
greener with less care. If using
chemicals, look for natural or biological ones first. Only apply
what is needed, and when needed,
following label directions. Make sure
your full service garden center or lawn professionals help you identify
the
problem correctly at the beginning.
Give thought to how you might reduce
mower use, which in turn will reduce gasoline use and carbon dioxide
emissions. These changes might include
electric or push mowers, (even rechargeable ones), reducing lawn size
(perhaps
with beds of groundcovers), and designing lawn edges properly. A
good lawn edge can reduce or eliminate the
need for gas-powered weed trimmers.
Consider design. If you have a large mown area, consider
letting it grow up with only high mowing once or twice a season.
You can regularly mow strips or high-traffic
areas, such as near the home and drives, to still have useful
recreation areas
and the effect of a mown lawn. Avoiding
sharp angles and cul-de-sacs, using curving lines instead, will reduce
time
needed to mow. Avoid "islands"
of turf surrounded by gardens or paving that take extra time to
mow. Plant these with flowers or groundcovers
instead.
More design ideas on using
groundcovers, and low-maintenance plants to choose, can be found in the
book by
Barbara Ellis, Covering Ground
(Storey Publishing).
Return to
Perry's Perennial
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