A
restoration allows you to improve
your lawn without removing the existing
turf. While restoring your lawn
is not nearly as labor intensive
as removing all of your turf and
starting over, it may still require
several weekends of work.
In
this section, each step of a lawn
restoration is described, some of
which are essential and others optional.
In most parts of North America,
the best time to begin restoration
is late summer or in fall, although
adjusting pH and dethatching can
be done in the spring to prepare
for a fall restoration.
Remove
Thatch and Weeds
When beginning a lawn restoration,
the first step is to remove any
thatch buildup -- even low levels
that would otherwise be acceptable.
Unless you can expose the soil between
the old grass plants, the steps
that follow will have poor results.
The
best time to dethatch is when your
lawn is thriving - not when it's
stressed in the heat of summer or
cold of winter. To begin, set the
height adjustment on your mower
to cut the grass about 1 inch or
so high, essentially half its normal
mowing height. Mow the entire lawn.
Short grass will make dethatching
and surface preparation easier.
if you will be overseeding it will
also improve seed germination rates
because more seed will make contact
with the soil and seedlings will
have greater exposure to the sun.
The
easiest way to remove thatch from
a lawn that is over 3,000 square
feet is with a power dethatcher,
which should be available at rental
stores. For smaller lawns or lawns
with a thin 1/2- to 1-inch layers
of thatch, a manual thatching rake
will do a satisfactory job. When
using a power dethatcher to remove
average amounts of thatch and to
scarify the soil, set the blades
to cut 1/8 to 1/4 inch into the
soil. Make several test passes on
an inconspicuous area of your lawn
to judge how much thatch (and turf)
will be removed. If too much or
too little is removed, raise or
lower the blades accordingly. The
spacing between blades can be adjusted
on some machines, but this is difficult
to do and so is best done by the
rental store staff. The blade spacing
for Bermudagrass and zoysiagrass
is 1 to 2 inches. Most rental store
owners will know the optimum settings
for the grasses grown in your area.
When
using a vertical mower to dethatch,
make several passes over the lawn
in perpendicular directions. It
is important to be thorough. Remove
the thatch you pull up after each
series of passes and add it to your
compost pile. When you have finished
dethatching, remow your lawn to
a height of 1 inch.
On
a lawn with thick thatch (more than
1-1/2 inches), you may need to partially
remove the thatch and allow the
lawn to fully recover before the
next dethatching session. Removing
too much thatch all at once can
do more harm than good. The rule
of thumb is to remove what you can
without tearing up holes of more
than a couple of square inches in
live turf. This may not be possible
on lawns with very thick thatch--more
than 2 inches. In that case, your
lawn may not be salvageable and
may need to be replanted from scratch.
See PLANTING
A LAWN
Fill
Depressions and Level Bumps
While you are dethatching your lawn,
check for bumps and depressions.
These may have been caused by poor
grading, uneven settling, or the
decomposition of buried tree stumps,
logs, or roots. Mark any irregularities
with latex spray paint so you can
find them easily when you are ready
to level them.
To
level small bumps, raise the sod
with a sharp spade or sodcutter
and remove the necessary amount
of soil beneath it. Cut out at least
a 2 by 2-foot section of sod. If
you lift smaller patches of sod,
they will likely dry out and die.
While the soil base is exposed,
mix in some compost and fertilizer.
Watersoak the area using a hose
and press the sod back into place.
Keep the area watered to prevent
lawn brownout.
Slight
depressions can be smoothed over
by topdressing: applying to the
surface a combination of topsoil
and compost. Native screened top
soil is recommended over top soil
sold in bags. Fill depression and
rake smooth with a landscape rake.
When handling larger depressions
- -those more than an inch or two
deep and several square feet in
area - raise the sod; fill the depression
with a mixture of screened native
top soil, humus, and fertilizer;
replace the sod, and press it in
place. Be sure to keep repaired
areas moist, or the edges will dry
out and turn brown.
Adjust
Your Soil's pH
Before applying anything, it is
best to test your own soil or obtain
test results from a professional
testing service or your local extension
agent. If your soil test shows that
the soil pH is low, add lime according
to the test recommendations. Pelletized
lime is the preferred type because
it is readily available and can
be safely, easily, and accurately
applied with a rotary spreader.
The
more clay and organic content in
your soil, the more lime you will
need to correct the pH. Sandy soils
require less lime to raise pH. If
you need to add more than 40 pounds
of lime per 1000 square feet to
correct your pH, do it in two or
more applications. And don't apply
lime with fertilizer mixed in the
same spreader. The resulting chemical
reaction will release the nitrogen
you want for your grass into the
air. After spreading lime, water
the lawn to wash the particles off
the grass leaves and into the soil.
rarely
is it that a lawn in Georgia clay
needs a lowering of pH. In the event
yourlawn does, add sulfur according
to you soil test recommendations.
Sulfur amendments are also available
in the form of compounds, such as
ammonium sulfate. These compounds
can be used in place of elemental
sulfur, but they can burn turf if
used in excess. See amendment packaging
for details on amounts that can
be safely applied to turfgrass.
Sulfur
acts within one month to lower soil
pH. To avoid applying too much,
don't try to make your correction
in one application. To meet recommended
amounts, make several surface applications
a few weeks apart and water the
grass after each application.
Add
Nutrients
When restoring a lawn, apply the
fertilizer recommended by the results
of your soil. Use a slow-release
fertilizer if possible, and avoid
putting down more fertilizer than
you need. Adding too much nitrogen
can cause rapid growth and a thinning
of plant cell walls, which makes
grass more susceptible to disease.
The excess fertilizer may also leach
and eventually find its way into
waterways, polluting them. If you
did not test your soil, apply a
slow-release fertilizer with an
Nitrogen-Phosphorus-Potassium ratio
of 3-1-2 or a natural, non-burning
fertilzer such as Milorganite,
which is rich in organic matter.
Build Organic Matter and
Microbe Numbers
The right dose of fertilizer won't
help much if your soil does not
contain an adequate population of
microbes, you need billions of these
microscopic organisms per handful.
Microbes not only digest grass clippings,
dead grass roots, and stems, but
they also make their nutrients available
to living grass plants.
To
have a thriving microbe population,
your soil must contain 2 to 5 percent
organic material. A topdressing
of compost, such as Claycutter or
Mushroom Compost, mixed with topsoil
followed by aeration will eventually
incorporate some organic matter
into the soil without disrupting
the lawn. When top dressing your
lawn, apply about one cubic yard
of Claycutter or other compost per
1,000 square feet. SEE: Making
Your Own Compost
Aerate
Your Lawn
Aeration, also called core cultivation
or aerifying, is an important part
of any lawn restoration program.
It allows grass roots to deeply
penetrate the soil, helps fertilizer
and organic matter get to roots,
allows oxygen to reach the roots,
and makes it easier for water to
soak into the soil. Simply aerate
once in the fall. Avoid aerating
during dry summer months because
you may damage an already stressed
lawn. There are several types of
aerating tools. Manual aerators
allow you to do small areas a little
at a time and to aerate corners
and other tight areas that are difficult
to reach with large equipment. You
supply the power for these tools
by pushing the hollow cylinders
or corers into the turf - much as
you would push in a spade. Small
power aerators work similarly and
are available at rental stores.
Some machines use a rotating tillerlike
action that pushes the corers into
the soil and extracts small plugs,
as the machines pull you forward.
These lawn mower-size machines will
fit into a full-size station wagon,
mini-van, or pickup truck and they
require two people to transport
them.
Avoid
aerators that only poke holes in
the lawn without removing plugs
because they are of less value to
your lawn. The largest aerators
will require a truck and several
helpers to transport them but do
a better job. With these machines,
the corers are vertically plunged
into the turf to extract a sizable
plug. You may opt to have a pro
tackle this job.
Aerators
penetrate your lawn best when the
soil has been moistened by rain
or watering; so, unless it rains,
water your lawn the day before aerating.
When aerating, make several passes
in several directions over every
square foot of lawn.
Prepare
the Surface and Overseed (If Necessary)
In the South, the best time to overseed
a Bermuda lawn starts in late spring
and goes through mid-summer. Starting
then gives the young grass plants
a better chance to germinate, establish
strong roots, and store food needed
for winter.
NOTE:
Overseeding hybrid Bermuda or Zoysia
lawns that were initially planted
using sod is not recommended. Only
overseed bermuda lawns that were
initially planted from seed.
Before
you begin, choose the seed that
was intially used to plant your
lawn. If you're not sure what type
was used visit a local nursery and
ask them about the best types of
Bermuda seed. At Wilson Bros Nursery
we are recommending 'Panama Turf-Type
Bermuda', which currently ranks
highest in color and turf density.
Panama Bermuda should be broadcast
using a hand-held spreader, with
micro-settings, at a rate of 1 pound
per 500 square feet.
TIP:
Do not use 'Common Bermuda' seed
as this grass is primarily used
for pastures.
For sowing grass seed, the recommended
approach is to apply seed to the
edges of the area you are sowing
first. Then divide your seed and
apply half while walking in one
direction, the other half while
walking in a perpendicular (opposite)
direction. Spread extra seed on
bare areas.
Finally,
follow up by applying a thin coat
(just enough to cover the soil)
of wheatstraw or hay to bare areas.
This mulch coating will help retain
moisture necessary for seed germination
and help to hold the seed in place
if there is heavy rain. Avoid putting
down a heavy layer that would inhibit
grass growth.
If
you have a lawn with grass that
spreads by stolons (aboveground
runners), such as Bermudagrass,
St. Augustine, zoysia or buffalograss,
you may introduce new grass plants
by inserting plugs or patches of
sod.
Care
for Young Grass Seedlings
Your work to this point will have
been in vain if you don't care for
the young grass plants as the seeds
germinate and begin to grow. The
most critical need is to apply water
at once or twice a day, depending
on the temperature and assuming
no rain. If the soil is allowed
to dry out, the seedlings won't
germinate or will soon wither and
die. To maximize the germination
rate, soak your lawn on the same
day you sow the seeds. On the next
day, assuming no rain, lightly sprinkle
the lawn for about 5 minutes morning
and afternoon. Be sure you have
moistened the soil to a depth of
one inch. Keep the overseeded lawn
moist until the young grass plants
are 2 inches tall by repeating a
light watering every day after periods
without rain. When the grass is
2 inches tall, resume normal watering
patterns.
Begin
mowing once the new grass reaches
2 inches. Use a sharp blade; a dull
one may tear up young grass plants.
Otherwise, stay off the seeded areas
except to fertilize once more. If
needed, apply the rest of the fertilizer
as recommended by your soil test,
or apply Milorganite
fertilizer.
SEE ALSO:
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