Centipedegrass for Florida lawns

Centipedegrass [Eremochloa ophiuroides
(Munro) Hack.] was introduced into the United States
from southeastern Asia. It is well-adapted to the
climate and soils of central and northern Florida and
is the most common home lawn grass in the
panhandle of Florida. Centipedegrass is a slow
growing, low maintenance grass with low fertility
requirements. Centipedegrass grows close to the
ground, is medium-textured and is naturally pale
green in color. Overfertilizing to obtain an unnatural
dark green color reduces its cold tolerance, increases
long-term maintenance problems, and is believed to
contribute to "centipedegrass decline."

Advantages

Centipedegrass does very well in acidic and infertile soils. It has fair to good shade tolerance and good drought tolerance. It can be established from seed, sod, or plugs and spreads by stolons. Maintenance and fertility requirements are low compared to other turfgrasses.

Disadvantages

Centipedegrass is highly susceptible to damage
from nematodes, particularly ring nematodes. This
damage limits the use of centipedegrass in south
Florida's sandy soils. It is also subject to attack from
insects called ground pearls. It has a naturally pale
green color and is prone to iron chlorosis. It has poor
salt, wear, and freezing tolerance. Stolons from
centipedegrass have a high lignin content and
contribute to a heavy thatch layer, particularly under
high fertility rates. The grass is often subject to
"centipedegrass decline," for which a causal agent has
not yet been identified. The decline is influenced by
management practices and is enhanced under high
fertility, high irrigation, and low mowing height
regimes. Intensive management over a period of 4 to
5 years results in root dieback in the spring. This condition is aggravated by thatch accumulation, which results in new stolons growing several inches above the soil surface. Proper management, with an emphasis on
maintenance of a viable root system, is the best
solution to this condition. This includes irrigation
during drought stress, maintaining a mowing height
of 1 1/2 - 2 inches, prevention of thatch accumulation,
and adherence to low fertility rates.

Varieties

Common

This is a low-maintenance cultivar that can be
established by seed or vegetative means. It grows
slowly and in a prostrate manner.

Oaklawn

This improved cultivar has better cold tolerance
than Common. It must be established vegetatively.

Centennial

This cultivar was also selected for cold tolerance.
Like Oaklawn, it requires vegetative establishment,
but is more tolerant of alkaline soils than Oklawn or
Common.

Tifblair

This cultivar was released by the University of
Georgia in 1997. It has good cold and freezing
tolerance, and can be propagated by seed or
vegetative means. It has a slightly faster rate of
growth than other centipedegrass cultivars.

TennTurf

Released by Tennessee in 1999, this cultivar has
the best cold tolerance of any centipedegrass. It is
currently available only as sod, sprigs, or plugs. It
prefers full sun but will tolerate some shade.
 

Maintenance of Centipedegrass

 

Centipedegrass can be established by seed,
plugs, sprigs, or sod. Planting centipedegrass as sod
will produce an instant lawn that will establish more
rapidly and be less susceptible to various stresses. Lay
the sod in a well-prepared seedbed, fitting the pieces
tightly together to avoid cracks in the turf. Wet the
Centipedegrass soil surface thoroughly prior to laying the sod. After the sod is in place water thoroughly and roll with a lightweight roller to ensure firm contact between the sod and soil. The entire area should be watered daily with 1/2 inch of water per application. Once the sod has rooted into the soil, irrigation frequency can be reduced to an as-needed basis. Although sodding is more expensive than seeding or plugging, good quality, weed-free sod will produce the best quality lawn.
 

Seed of centipedegrass is expensive, but the
seeding rate is low and this method of establishment
is probably cheaper than vegetative planting if time
and labor are considered. The suggested seeding rate
is 4 ounces per 1000 square feet. The best time to
seed is during the period from April to July, since this
permits a full growing season before winter weather.
Fall seeding is undesirable because the young
seedlings may not become sufficiently established to
withstand cold injury during the winter.
Centipedegrass seed is naturally slow to germinate,
and may take up to 2 to 3 weeks. Soil washing due to
heavy rain or excessive irrigations should be
minimized by lightly mulching the planted area. Seed
quality should be considered when purchasing seed
for planting. Insist on seed with a purity of 90% or
better and a minimum of 85% germination.
Plugging or sprigging centipedegrass will leave
open areas of soil, which are subject to invasion by
fast growing, opportunistic weed species. Due to the
slow growth habit of centipedegrass, diligent weed
control measures will have to be used if this method
of planting is used.
The best time to establish centipedegrass is
during the spring or early summer months. This will
enable the grass to grow in before cooler weather
begins, when growth will be reduced. Seed may
safely be sown until later in the year, but growth will
again be greatly reduced in the fall. When
establishing any grass, it is important to provide
irrigation more frequently than is normally
recommended. Until a viable root system is
established, turf demands for irrigation are greater. It
is also important not to now until the roots have had a
chance to work down into the soil and establish
themselves there.
 

Proper site preparation before planting is critical
to ensure successful establishment. Refer to the
chapter on "Preparing to Plant a Florida Lawn" for
complete information. Centipedegrass is best adapted
to a soil pH of 5.0 to 5.5. Severe iron chlorosis may
occur if pH is above 6.5 to 7.0. Preplant application
of wettable sulfur at the rate of 430 pounds per acre
(10 pounds per 1000 square feet) can be used to
lower the pH of some Florida soils 1 pH unit. Do not
apply more than 10 pounds per 1000 square feet of
wettable sulfur per application. Where more is
required, allow 60 days between applications. Irrigate
with 1 inch after each application to activate the
sulfur. Lime is seldom required for centipedegrass.

Fertilizing

 

Proper fertilization of any lawngrass is an
important component of the best management
practices of your home lawn. Fertilization and other
cultural practices can influence the overall health of
your lawn, and can reduce its vulnerability to
numerous stresses, including weeds, insects, and
disease.
 

It is advisable for homeowners to have soil tests
done annually. Your local Cooperative Extension
Service office has recommendations and bags for
taking soil samples and submitting to the Extension
Soil Testing Lab for analysis. In particular,
phosphorous levels are best determined by soil
testing. Since many Florida soils are high in
phosphorous, little or no phosphorous may be needed
for satisfactory lawn growth.
 

Established centipedegrass lawns have very low
fertility requirements. Centipedegrass is a
low-maintenance turfgrass and does not respond will
to excessive use of fertilizer, especially nitrogen. Do
not overfertilize centipedegrass with nitrogen to equal
the color of St. Augustinegrass. Overfertilization of
centipedegrass can result in centipedegrass decline,
insect pressure, and thatch accumulation. As with any
lawn grass, do not apply more than 1/2 lb. of water
soluble nitrogen per 1000 square feet at any one time.
Up to 1 lb. of nitrogen per 1000 square feet may be
applied at one time, but at least 50% of that nitrogen
should be in a slow-release form.
 


In general, two weeks following spring
regrowth, apply a complete fertilizer such as 16-4-8 at
the rate of 1/2 (water-soluble) to 1 (slow-release)
pound of nitrogen per 1000 square feet. The three
numbers refer to percent nitrogen, phosphorus, and
potassium, respectively, in the bag. For example a
50-pound bag of 16-4-8 contains 16% nitrogen or 8
pounds total nitrogen. This bag will fertilize 8000
square feet at the rate of 1 pound of nitrogen per 1000
square feet. University of Florida guidelines for
lawngrass fertility show a range of fertilizer rates
over which a particular species may be successfully
grown for various areas of the state. These ranges are
included to account for individual homeowner
preferences for low-, medium-, or high-input grass.
Additionally, localized microclimate effects can have
a tremendous effect on turfgrass growth, and a range
of rates provides more opportunity to allow for these
environmental variations. An example of this would
be a typical home lawn that is partially shaded and
partially sunny. The grass growing in the shade
should receive lower rates of fertilizer than that
growing in full sun.

 

All rates are in pounds of nitrogen per 1000 square feet. For questions on how to apply these amounts, refer to the section in this book entitlited Florida Fertilization.
Fertilizer should be applied to centipedegrass in 1
to 3 applications for spring greenup through fall. Do
or apply nitrogen too early in the growing season,
particularly in north Florida, or subsequent frosts
may damage the grass. Likewise, don't fertilize too
late in the year, as this can slow regrowth the
following spring. If applying water-soluble forms at
the lower application rate, it will take more
applications to apply the total amount of fertilizer
needed for the year than if applying a slow-release
fertilizer form.
 

As mentioned previously, one of the common
problems of centipedegrass is a yellowing called
chlorosis, which is usually caused by iron deficiency.
This condition is most severe where soil pH is high
(above 6.5) or where the soil contains large quantities
of calcium or phosphorus. This yellowing is
generally most severe in early spring, when daytime
temperatures are warm but nighttime temperatures
are still cool. Warm daytime air temperatures
promote leaf and stolon growth, but cool nighttime
temperatures limit root growth. The roots then cannot
assimilate enough nutrients to supply the growing
leaves, and the leaves turn yellow. As soils become
warmer, this temporary nutrient deficiency
disappears. Avoid using excessive phosphorus
fertilizers unless soil test results indicate to do so.
Iron chlorosis can be controlled by several methods.
Soil pH can be lowered by regular use of
acid-forming fertilizers such as ammonium nitrate or
ammonium sulfate. These will render the iron more
available to the grass. If the soil is naturally iron
deficient, iron fertilization is necessary.
Centipedegrass usually responds well to supplemental
applications of iron. Chelated or ferrous sulfate iron
can be applied evenly and easily with a hose-end
applicator. Apply the ferrous sulfate at the rate of 2
ounces in 3 to 5 gallons of water per 1000 square feet.
Consult the label for chelated iron rates. Fertilizers
containing iron and a combination material of
ammonium sulfate and ferrous sulfate are also
available.
 

Do not apply nitrogen too late in the growing
season, as this can slow regrowth the following
spring. A general guideline for the last fertilizer
application is mid-September for north Florida, early
October for central Florida, and late October for
south Florida. It is possible to apply potassium at a
rate of 1 pound of potassium per 1000 square feet.
This will help the grass to overwinter, tolerate cold
temperatures, and green-up quickly in the spring.

Mowing

 

Proper mowing practices are necessary to keep
any lawn healthy and attractive. Centipedegrass that
is actively growing should be mowed every 7 to 14
days at 1.5 to 2 inches in height. Mowing at this
height promotes a deeper, more extensive root system
that enables the grass to better withstand drought and
nematode stress. Remove no more than 1/3 of the
height of the leaf blades with any mowing (e.g., for a
lawn to be maintained at 2 inches in height, mow
when the turf reaches 3 inches). It is important not to
mow centipedegrass at lower heights, as that will
reduce the tolerance of the grass to heat, drought,
nematodes, and many other stresses. It will also
suppress root growth.
 

Clippings should be left on the ground after
mowing. They do not contribute to thatch build-up, as
is often assumed, but are actually readily degraded by
microorganisms. They also provide a source of
nutrients to the lawn, and can reduce fertility
requirements if left on the lawn on a regular basis. A
sharp and well-adjusted rotary or reel mower should
be used.

Watering

 

Irrigation on an as-needed basis is an excellent
way to water any grass, provided the amount of water
is applied when needed. Irrigation is needed when
leaf blades begin to fold up, to actually wilt, to turn
blue-gray in color, or when footprints remain visible
after walking on the grass. Apply 3/4 inch of water per
application, which will apply water to the top 8
inches of soil, where the majority of the roots are. To
determine rates from a sprinkler system, place several
coffee cans throughout the irrigation zones to find out
how long it takes to apply 3/4 inch of water. During
prolonged drought, irrigation may be needed more
often. Centipedegrass has good drought tolerance and
will usually recover from severe drought injury soon
after rain or irrigation. Do not overwater
centipedegrass lawns as this weakens the turf and
encourages weeds.


During extended periods of drought,
centipedegrass may go dormant if left unirrigated.
The grass will turn brown and stop growing during
this dormant period, but will revive and resume
growth upon irrigation with sufficient amounts of
water.

 

Information provided by the University of Florida's IFAS Extension