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St. Augustine Lawn Grass Repair or Replacement
St. Augustine Lawn Grass Seed is NOT AVAILABLE from any source!
***St. Augustine grass varieties do not
produce a harvest-able seed. St. Augustine varieties are available in
sod, sprigs or plugs only. Due to high maintenance cost and increase
water restrictions many home owners are converting their St. Augustine
lawns to more drought tolerant lower maintenance lawn grass varieties
such as Argentine Bahiagrass, Zoysia, Centipede and Premium Bermuda
grass varieties***
Are you one of the many home owners suffering from St. Augustine Lawn Grass Problems?
Throughout
the past thirty years Hancock Farm & Seed Company has assisted
thousands of people to replace their old St. Augustine lawns with
grass varieties that are more drought resistant, insect resistant and
require little maintenance.
Our most popular lawn grass seed variety for repair or replacement of St. Augustine lawn grass is Argentine Bahiagrass. The appearance and durability of Argentine Bahiagrass and St. Augustine are very similar. Argentine Bahiagrass requires less than 1/2 of the water to maintain a lush green appearance. This
is great for the environment and for your pocket! To view all the
available lawn grass varieties that are commonly used to replace St.
Augustine please use the link below.
CLICK HERE TO VIEW OUR LAWN GRASS SEED PRODUCTS!
Argentine Bahia Lawn Grass Seed -
St. Augustinegrass for Florida Lawns
St. Augustinegrass (Stenotaphrum secundatum
[Walt.] Kuntze.), is widely adapted to the warm, humid (subtropical)
regions of the world. It is believed to be native to the coastal
regions of both the Gulf of Mexico and the Mediterranean. In Florida,
St. Augustinegrass is the most commonly used lawngrass throughout the
state. It can grow satisfactorily in a wide variety of soils.
AdvantagesSt.
Augustinegrass produces a green to blue-green dense turf that is well
adapted to most soils and climatic regions in Florida. It has
relatively good salt tolerance and certain cultivars possess good shade
tolerance. Establishment of St. Augustinegrass from sod is quick and
easy. There are several cultivars commercially available.
DisadvantagesSt.
Augustinegrass, like most turfgrasses, has certain cultural and pest
problems. It does not remain green during drought conditions without
supplemental irrigation. It produces thatch under high fertilization
and irrigation regimes. It has poor wear tolerance and will generally
not stay green throughout the winter months in many parts of the state.
The coarse leaf texture of most cultivars is objectionable to some
people. The major insect pest of St. Augustinegrass is the chinch bug,
and there are currently no chinch bug resistant cultivars available.
Grubs can also be a major insect pest. Some cultivars are also
susceptible to diseases such as gray leaf spot, brown patch, take-all
patch, and root rot. Additionally, there are no herbicides available to
control hard-to-kill grass-type weeds that may become established in
the turf.
CultivarsThere
are several cultivars of St. Augustinegrass available for lawn use in
Florida. The different cultivars vary in their tolerances to
environmental stresses and susceptibility to pests. Table 1 lists some
relative growth characteristics for currently available cultivars.
'Amerishade''Amerishade'
is a true "dwarf" cultivar of St. Augustinegrass, with a very slow and
prostrate growth habit and a lower mowing height (1.5 to 2 inches) than
standard cultivars. Its mowing frequency is less than those of most
other St. Augustinegrass cultivars, with research showing that it can
go for just over two weeks even in the summer months before needing
mowing. Like the other dwarfs, it has an increased tendency to produce
thatch and is very susceptible to disease. It does not perform well in
the northern parts of the state and can experience winterkill during
cold years. Due to its slow growth habit, it also has greater
difficulty recovering from damage or injury in comparison to other St.
Augustinegrass cultivars. It maintains a deep green color and has good
shade tolerance.
'Bitterblue''Bitterblue'
is a variety that was selected in the 1930s. Although 'Bitterblue' is
marketed as a certified cultivar, there is no certified 'Bitterblue'
germplasm maintained by turfgrass breeders at this time. What is
typically sold as 'Bitterblue' has a fine, dense texture and dark
blue-green color. It has good cold and shade tolerance, but is not
resistant to chinch bugs or gray leaf spot disease. It is also
susceptible to the herbicide atrazine, making weed control difficult.
It is what is referred to as a "standard" cultivar, with a mowing
height of 3.5 to 4 inches.
'Classic''Classic'
is a proprietary cultivar released in the early 2000s by Woerner Turf.
It has good cold tolerance and is being used in north Florida and other
states. The grower claims it has good shade tolerance, but this has not
yet been verified by university research and there is no evidence that
it is superior to other cultivars. It is a "standard" cultivar and
should be mowed at 3.5 to 4 inches. It has a dark green color.
'Delmar''Delmar'
is a dwarf cultivar that is often sold as sod or plugs. It has good
shade tolerance and also does well in full sun. It has short
internodes, a dark green color, and good cold tolerance. It should be
mowed at 1.5 to 2.5 inches. 'Delmar' is susceptible to chinch bugs, sod
webworms, and brown patch disease. Like the other dwarfs, it has a
tendency to become thatchy.
'DeltaShade''DeltaShade'
is a proprietary release from Environmental Turf in 2005 and is
currently in production in sod fields. It is a "standard" cultivar and
should be mowed at 3.5 to 4 inches. University research shows that
'DeltaShade' has good shade tolerance, but not as good as the dwarf
varieties. It appears to have good cold tolerance, although no
university studies have been done to verify this. In some landscapes,
it tends to have a lighter green color than some cultivars.
'Floralawn'This
cultivar was released in 1986 by the Florida Agricultural Experiment
Station. It has poor shade and cold tolerance and has a coarse leaf
texture. 'Floralawn' performs best in mild environments in full sun to
moderate shade. It is not widely grown or used but is one of three
cultivars currently available as a certified variety.
'Floratam''Floratam'
is an improved St. Augustinegrass that was released jointly in 1973 by
the University of Florida and Texas A & M. 'Floratam' is the most
widely produced and used St. Augustinegrass in Florida. It is a
coarse-textured cultivar that has poor cold and shade tolerance
relative to other St. Augustinegrass cultivars. It will not persist
well in environments that receive less than 6 hours of sunlight daily.
It grows vigorously in warm weather, but has a relatively long period
of dormancy in north Florida and greens up more slowly in the spring
than some cultivars. When first released, it had UF-documented chinch
bug resistance, although that has largely been lost over time and
chinch bugs are now a major pest of 'Floratam'. It is also susceptible
to gray leaf spot and other diseases. 'Floratam' is intolerant of
atrazine herbicides when temperatures are above 85°F. It is a
"standard" cultivar and should be mowed at 3.5 to 4 inches. 'Floratam'
is available as a certified cultivar.
'Floratine'This
is an improved selection that was released in 1962 by the Florida
Agricultural Experiment Station. It has a finer leaf texture and a
denser and shorter growth habit that allows closer mowing than other
standard St. Augustinegrass cultivars. It is not resistant to chinch
bugs but tolerates light to moderate shade. 'Floratine' is similar to
'Bitterblue' in many characteristics and the two are difficult to
distinguish.
'Palmetto''Palmetto' was
a selection found by a Florida sod grower in 1988 and was released in
the mid 1990s by Sod Solutions. It is of intermediate growth, with
shorter leaf blades and internodes than many other cultivars, but is
slightly larger than the dwarf St. Augustinegrass cultivars such as
'Seville' and 'Delmar'. It has a nice growth habit and does well in
full sun or partial shade, but not in dense shade. It is sometimes
referred to as drought-tolerant, but research has not shown that it has
any greater degree of drought tolerance than other St.
Augustinegrasses. It often has problems with disease, particularly in
Florida's humid environment. It tends to have a lighter green color
than many other cultivars.
'Raleigh''Raleigh'
is a cold-hardy cultivar released by North Carolina State University in
1980. It has a medium green color with a coarse texture. It is
susceptible to chinch bugs and brown patch disease, but can be planted
in northern Florida due to its tolerance to lower temperatures. During
peak summertime heat, 'Raleigh' has been noted to yellow and to grow
less aggressively than it does at cooler temperatures. Supplemental
iron applications can reduce this yellowing tendency. 'Raleigh' is best
adapted to the heavier, organic, clayey soils with medium to low soil
pH in north and northwest Florida.
'Seville''Seville'
is a dwarf, fine-leaved variety with a dark green color and a low
growth habit. It is susceptible to chinch bug and webworm damage. Like
the other dwarf cultivars, 'Seville' tends to be thatch-prone.
'Seville' performs well in both shade and full sun, but is
cold-sensitive. 'Seville' should be mowed at 2 to 2.5 inches. It is not
as common as 'Delmar', but is also a good choice for shady sites.
Other VarietiesSeveral
other lesser-known and available St. Augustinegrass varieties have been
released. These include 'Mercedes' and others. Research performed on
these varieties has been limited, and generally they have not proven
superior to older varieties that are currently available.
Maintenance of St. AugustinegrassProper
lawn maintenance practices are the best means for avoiding pest
problems and obtaining a high-quality lawn. St. Augustinegrass will
require inputs of fertilizer to maintain a nice green color and healthy
growth characteristics. During certain times of the year, it may
require irrigation, however, this may not be the case year round.
Pesticides may be needed periodically, but their use can be minimized
if other cultural practices (mowing, irrigation, fertilization) are
done correctly.
EstablishmentAlthough
St. Augustinegrass can be planted year-round in warmer sections of
Florida, the best time to plant is when environmental conditions allow
for rapid establishment. Allowing the grass to establish and develop a
deep root system before it experiences temperature extremes will help
it establish more quickly and with less water. In south Florida, the
optimal time for establishment is during late fall, winter, or spring.
In central and north Florida, avoid establishment during cold winter or
hot summer months.
It is
important to provide frequent irrigation when grass is establishling.
Multiple, short irrigations throughout the course of the day for 7 to
10 days following planting will help the grass establish. After the
roots have pegged down, cut back frequency to once a day and increase
the time to 1/4 to ½ inch for another 7 days. After this, reduce
frequency to 2 to 3 times weekly, again applying ¼ to ½ inch of water.
Three to 4 weeks after sodding, the grass should be fully established
and irrigation can begin on an "as-needed" basis. For more information
on this, see ENH 860 "Irrigation and Fertilization Requirements of
Lawns and Landscapes."
Do not mow
the lawn until the roots have had a chance to peg down into the soil,
generally about 10 to 14 days after planting. Pegging means that the
sod cannot be lifted without appreciable force. For more information on
preparing the site and establishment, refer to ENH03 "Establishing Your
Florida Lawn."
St.
Augustinegrass is established by vegetative propagation such as sod,
plugs, or sprigs. Vegetative propagation means that instead of seeds,
plant parts with growing points are used for planting. St.
Augustinegrass has stolons (above-ground stems) that have areas of
actively dividing cells at the nodes. These areas are capable of
generating new shoot growth and are responsible for lateral growth of
St. Augustinegrass along the ground.
SoddingSodding
is the instant method of establishment because it will produce an
instant lawn. Although covered, the grass is still perishable at this
stage. It is not yet safe for play or other activities and still needs
to knit-in and root into the soil. Sodding reduces potential weed
competition that is observed when using other planting methods that
leave bare ground. Sod should be laid over bare moist soil with pieces
laid in a staggered bricklike pattern and the edges fitted tightly
together to avoid any open cracks. Rolling and watering thoroughly will
ensure good contact with the soil for fast rooting.
SpriggingSprigging
is less expensive than sodding, but does not produce an instant lawn as
does sodding. Sprigs contain nodes on stolons, which are planted
end-to-end in furrows 6 to 12 inches apart. Stolons should be covered
with soil, but leaf blades should be left exposed. The soil should be
tamped and thoroughly saturated. Soil needs to be kept moist until
growth of shoots and roots begins.
PluggingA
number of St. Augustinegrass cultivars are available commercially in
garden centers as plugs. Sod also can be made into plugs by cutting it
into small squares. Spacing of plugs varies from 6 to 24 inches. The
closer spacing provides full coverage more quickly. Plugs are placed in
holes of the same size or in open furrows and tamped into place. A
thorough watering completes the installation. The turf should then be
cared for like a sprigged lawn.
FertilityProper
fertilization of any lawngrass is an important component of the best
management practices for your home lawn. Fertilization and other
cultural practices influence the overall health of your lawn and can
reduce or increase its vulnerability to numerous stresses, including
weeds, insects, and disease. If you apply your own fertilizer to your
lawn, please note that any fertilizer that is over-applied or does not
get to the target has the potential to move as either leachate through
the soil or as runoff on top of the soil. When this happens, nonpoint
source pollution can result and this can have a direct effect on
surface and ground water quality. Refer to ENH979 "Homeowner Best
Management Practices for the Home Lawn" for more information on how to
properly apply fertilizer.
Maintaining a
good-quality lawn requires a properly planned fertility program. An
acceptable- quality St. Augustinegrass lawn can be grown with a low to
high level of fertility, depending on what the homeowner wants. First,
decide how much time and effort can be spent on lawn maintenance. A
lower-fertility lawn is best for those with little time to spend on
lawn care. A high-fertility lawn may be better suited to those who
desire a manicured appearance for their yard. This type of maintenance
will require more time and money for lawn care.
In general,
two weeks following spring regrowth, apply a fertilizer at the rate of
½ (water-soluble) to 1 (slow-release) pound of nitrogen per 1000 square
feet. Homeowners applying their own fertilizer should look for a
fertilizer with at least some of the nitrogen in slow-release form.
Nitrogen is the first number on the bag and you will find a wide range
of variation in percentage of nitrogen among commercial fertilizers.
What fertilizer you choose is up to you, but read the label to learn as
much as possible about the nutrients in your fertilizer. Lower N
analysis fertilizers mean that more material must be applied to provide
the rate of N suggested above to the 1000 sq. ft area and may aid some
people in distributing the material uniformly. Look at the label on the
bag for a breakdown of nutrient sources and what percent is in slow
release vs. quick release (also called water soluble) nitrogen. Also
watch for low phosphorus (second number on the bag). Many Florida soils
are high in plant-available phosphorus and your lawn may not require
any additional phosphorus in the form of fertilizer. Look for a
fertilizer with 0, 1, or 2% phosphorus unless you have done a soil test
indicating that your lawn needs additional phosphorus. The third number
on the bag is potassium. This may be present in levels equal to or less
than nitrogen. Examples of good analyses for a turf fertilizer include
15-0-15, 15-2-15, etc.
It is
important that any fertilizer be applied to supply the correct amount
of nitrogen. Table 1 provides a breakdown of how much of many commonly
available fertilizers should be applied to provide ½ lb. of N per 1,000
square feet. For more information on fertilizer, refer to ENH 962,
"Figuring out Fertilizer for the Home Lawn."
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 microclimatic effects can have a
tremendous effect on turfgrass growth, and a range of rates allows 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. The guidelines are also separated into three
geographical locations statewide as indicated in the table below. All
rates are in pounds of nitrogen per 1000 square feet.
Fertilizer
should be applied to St. Augustinegrass in 2 to 6 applications from
spring green-up through fall. Do not apply nitrogen too early in the
growing season, particularly in north Florida, or late-season frosts
may damage the grass. Likewise, don't fertilize too late in the year
because this can slow regrowth the following spring. If you use
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 you use a slow-release fertilizer form.
It is
advisable for homeowners to have soil tests done annually. Your local
cooperative extension service office has instructions and supplies for
taking soil samples and submitting them to the Extension Soil Testing
Laboratory for analysis. In particular, phosphorus levels are best
determined by soil testing. Since many Florida soils are high in
phosphorus, little or no phosphorus may be needed for satisfactory lawn
growth.
On high-pH
(>7.0) soils or where high-pH water is applied, yellow leaf blades
may be an indication of iron or manganese deficiency. For iron
deficiency, spray ferrous sulfate (2 ounces in 3 to 5 gallons of water
per 1000 square feet) or a chelated iron source (refer to the label for
rates) to temporarily enhance color. Iron applications every 6 weeks
will help maintain green color and, unlike nitrogen, will not promote
excessive top growth. On high-pH soils (>7.0) or where high-pH
(>7.0) water is applied, manganese deficiency may also become
evident. Lower the soil pH by applying 15 pounds of elemental sulfur
per 1000 square feet prior to grass establishment. Once the grass is
established, up to 5 pounds of elemental sulfur may be added per 1000
square feet, if it is immediately irrigated into the soil to prevent
burn. Using ammonium nitrate or sulfate as a fertilizer source will
also help to temporarily reduce soil pH. Apply manganese as a
fertilizer with micronutrients or as straight manganese sulfate (MnSO4) bimonthly at 0.41 pound per 1000 square feet (18 pounds per acre) to relieve deficiency symptoms, if present.
Mowing
Proper mowing
practices are necessary to keep any lawn healthy and attractive.
Standard St. Augustinegrass cultivars ('BitterBlue', 'Classic',
'Floratam', 'Floratine', 'Palmetto', etc.) should be maintained at a
height of 3.5 to 4 inches. Repetitively mowing at lower heights reduces
overall stress tolerance of the lawn, discourages deep rooting,
increases the chance for scalping if a mowing event is missed or
postponed due to weather, and may increase susceptibility to pest
problems. To obtain the correct height with most home rotary lawn
mowers, use the highest wheel height setting. Maintaining the right
height will help the grass develop a deep root system and give a better
appearance to the turf. No more than a third of the leaf blades should
be removed with any mowing. If possible, increase mowing height during
periods of moisture stress or if the grass is growing in shade. Newer
semidwarf varieties have a lower growth habit, and should be mowed at 2
to 2.5 inches for optimum quality. Mowing too infrequently and watering
improperly can cause a thatch buildup.
A rotary
mower can be used on St. Augustinegrass. It is important to keep the
blades sharp and well-adjusted to get a clean cut. Dull blades will
give the lawn a brownish cast, because a ragged cut shreds the leaf
blades rather than cutting them. During the growing season, blades
should be sharpened monthly. St. Augustinegrass will require mowing
weekly during the growing season and less often during cooler months of
the year. In north Florida, mowing may not be required during winter
months.
Grass
clippings should be left on a lawn that is mowed at the proper height
and frequency. Under these conditions, clippings do not contribute to
the thatch layer. Clippings put nutrients back into the soil system and
may reduce turf fertilization requirements by up to 25%. If clippings
are excessive (e.g., clumping occurs), let them dry out and then
disperse them over the lawn.
WateringThe
best way to irrigate an established lawn is on an as-needed basis.
Grass blades will begin to wilt (e.g., fold, turn bluish-green in
color, and not recover from traffic or footprints) as the moisture
begins to be depleted in the soil. If the lawn shows signs of slight
wilting, it is time to irrigate with ½ to ¾ inch of water. Do not water
again until the lawn shows signs of wilting. The amount of water
applied should not vary, but the frequency with which your lawn needs
water can vary due to season, soil type, grass species, temperature,
etc. For further information on recommended watering practices, refer
to ENH9 "Watering Your Florida Lawn" and ENH63, "Let Your Lawn Tell You
When to Water."
Proper
watering practices will help maintain a lawn that requires less mowing
and has little thatch buildup. Proper watering will also help develop a
deep root system and make the lawn less susceptible to damage by pests
and environmental stresses. If the diseases brown patch or gray leaf
spot are a continuous problem, excessive watering and nitrogen
fertilization may be responsible. Certain weeds, such as dollarweed and
sedges, also thrive in soils that are continuously wet.
Pest ProblemsOther
factors can also decrease the quality of a lawn. Excessive shade,
compacted soils, overwatering, improper mowing, traffic, and high or
low pH can all cause a lawn to perform poorly. It is important to
recognize what the source of the problem is and to correct it if
possible. For more information on these types of stresses, refer to
ENH153, "Environmental Stresses and Your Florida Lawn."
WeedsThe
best approach to weed control is a healthy, vigorous lawn. Weed
problems in a lawn indicate that the turf has been weakened by improper
management practices or damage from pests. Proper management practices
can eliminate most weed problems. If weeds are a persistent problem,
herbicides labeled specifically for St. Augustinegrass should be used.
If an herbicide is needed, apply preemergence herbicides (i.e.,
pendimethalin, benefin, bensulide, atrazine, or others) to control
crabgrass if it was present in previous years. Timing is critical for
successful control. As a general rule, apply Feb. 1 in south Florida,
Feb. 15 in central Florida, and March 1 in north Florida. Note: Preemergence herbicides will not control weeds that are actively growing.
Apply
postemergence herbicides (e.g., atrazine) as needed for control of
summer annual and perennial broadleaf or grassy weeds. Do not apply
these materials if the turf is under moisture stress or if air
temperatures exceed 85°F. Check with your local county cooperative
extension office for positive weed identification and latest
recommendations.
Many
commercial "weed-n-feed" formulations will provide control, but they
should be used with caution because certain plant materials may not be
tolerant. These herbicides can damage landscape plants whose roots may
extend far under the lawn. Carefully read the label before use and
follow all label directions. Refer to ENH884, "Weed Management in Home
Lawns" for more information.
Insects
The major
pest of St. Augustinegrass is the chinch bug . These are foliar-feeding
insects that suck plant juices through a needlelike beak, causing
yellowish to brownish patches in turf. Injured areas are usually first
noticed as the weather begins to warm, in areas along sidewalks,
adjacent to buildings, and in other water-stressed areas where the
grass is in full sun.
Check for
chinch bugs by removing the ends of a coffee can, inserting one end
into the soil at the margin of suspected damaged areas, and filling
with water. Chinch bugs will float to the water surface within five
minutes. In areas where chinch bugs are a serious problem, a single,
thorough insecticide treatment may offer only temporary control.
Therefore, repeat applications may be required. Some populations of
this insect have become resistant to synthetic pyrethroid insecticides.
Other insect
pests, including webworms, armyworms, grass loopers and mole crickets
can damage St. Augustinegrass. Mole crickets damage turfgrass areas
primarily by creating tunnels or soft mounds while searching for food.
Additional damage may result from small animals digging through the
soil profile in search of the mole crickets as food. Check for mole
crickets by (1) examining an area for the tunnels, or (2) applying 2
gallons of water mixed with 1½ ounces of detergent soap per 2 square
feet in suspected damaged areas. Mole crickets will surface in several
minutes.
White grubs
are another pest of St. Augustinegrass. These can be found by lifting
the grass to a depth of about two inches. Grubs will be seen feeding on
the roots at this level. For more information on insect control, refer
to ENY300, "Insect Pest Management on Turfgrass."
Diseases
Brown patch
and gray leaf spot are two major disease problems of St.
Augustinegrass. Brown patch occurs in warm, humid weather and is
encouraged by excessive nitrogen. Brown patch is generally most
noticeable during spring and fall months. Gray leaf spot occurs during
the summer rainy season and is primarily a problem on new growth. Both
diseases can be controlled with fungicides.
Other St. Augustinegrass disease problems originate in the root system. Take-all root rot (Gaeumannomyces graminis var. graminis)
occurs under high moisture or stress conditions. When symptoms are
noticeable aboveground, the disease is usually in an advanced state.
Following proper cultural practices is the best defense against this
disease. Refer to SS-PLP-14, "Turfgrass Disease Management" for more
information.
NematodesSeveral
types of nematodes infest St. Augustinegrass lawns. Population peaks of
nematodes typically occur in late April to early May and again in late
August to early September. Damage symptoms include thin stand density,
less vigorous growth, a weakened root system, slow recovery following
rain or irrigation application, and certain weed invasions (e.g.,
prostrate spurge and Florida pusley). Soil nematode levels can only be
positively identified through laboratory procedures. Your local county
Extension service office can provide information on submitting soil
samples to the University of Florida Nematode Assay Laboratory. There
are currently no effective nematode controls for use in the home lawn.
Cultural controls include encouraging deep turfgrass rooting by raising
the mowing height, irrigating less frequently but more deeply, and
providing ample soil potassium. For more information on nematodes,
refer to ENY006, "Nematode Management in Residential Lawns."
Other ProblemsMany
other factors can decrease the quality of a lawn. To ensure a good St.
Augustinegrass lawn, refer to other sections of this publication for
recommended management practices, and follow label directions when
applying fertilizers and pesticides.
Thatch Removal
Thatch is the
layer of undecomposed leaf blades, stolons, roots, and crowns
intermingled with soil. Leaving mowing clippings on the lawn does not
cause thatch because clippings are readily broken down by microbes in
the soil. Thatch development is greatest in grass that is
overfertilized, overwatered, and improperly mowed. An excessive thatch
layer will reduce water penetration and can bind up fertilizer or
pesticides. In severe cases, you may see roots actually growing above
ground and rooting into the thatch layer. This is a very unhealthy
condition and leaves a lawn vulnerable to many stresses.
If the thatch
layer exceeds 1 inch, remove by vertical mowing, or "verticutting" in
early spring to mid summer. Verticutting uses vertical blades that
slice through the thatch and slightly into the soil, which results in
much of the dead material being removed to the top of the lawn. A
3-inch spacing between the de-thatching blades is best for St.
Augustinegrass. Caution: Vertical mowing may result in damaged turf
that will require a period of recuperation. Do not attempt vertical
mowing unless the grass is actively growing. Verticut in an east to
west or north to south pattern but not in all four directions. A
professional landscaping maintenance service or the local county
cooperative extension service office should be consulted before
attempting lawn renovation. Remove debris by raking, sweeping, or
vacuuming, and follow with a conventional mowing to improve turf
appearance. Immediately irrigate to prevent root zone dehydration. One
week after vertical mowing, apply 1/2 pound of soluble nitrogen per
1000 square feet to encourage recovery. This material must be watered
into the soil immediately following application to prevent plant burn.
Periodic topdressing (adding a uniform layer of soil on top of the
grass) with ¼ inch of soil similar to that underlying the turf is the
best method to alleviate thatch accumulation; however, the physical
labor required limits the practicality of this method for most
homeowners. If topdressing, be sure to use soil that is free of weed
seeds and nematodes. Do not exceed recommended topdressing rates, as
this encourages brown patch disease.
RenovationReplant
large, bare areas by broadcasting sprigs (1 bushel per 1000 square
feet), by planting 2-inch plugs every 12 inches, or by sodding. Keep
these areas continuously moist with light, frequent irrigations several
times daily until runners develop or sod is well-rooted. Over time,
gradually reduce irrigation frequency but increase irrigation duration
to apply ½ to ¾ inch of water. Refer to ENH03 "Establishing Your
Florida Lawn" for more information.
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