Fescue lawns are called "cool season" grasses because they grow
most actively during the cooler times of the year, going
semi-dormant in the hotter months. Generally "cool season" turf
grasses do poorly in Cumberland County and are not recommended.
They have a tendancy to go dormant in the hot months of July,
August and September. A combination of turf-type
tall Fescue and Kentucky bluegrass varieties will come closest to
giving year-round green in Northern Cumberland County. Do not
attempt to grow both
cool-season and warm-season grasses
in
the same lawn. Their cultural needs are exactly opposite and
neither will thrive. A successful fescue lawn depends largely on
WHERE, WHAT, WHEN and HOW you manage it.
Soil Test: Only a soil test can determine your lime and
fertilizer needs, and soils should be tested every 2-3 years.
The NC Department of Agriculture performs this test free of
charge. Boxes and instructions are
available at the Extension Service Office. In the absence of
precise information, a rule of thumb approximation is to add 20
lb. of 10-10-10 fertilizer combined with 4 pounds of 0-46-0
(triple superphosphate) and 75 lb. of dolomitic lime per 1000 sq.
ft. The desirable pH for fescue lawns is 6.5 to 7.0. The
naturally occurring pH for the Cumberlabd County area is 4.5 to
5.3,
strongly to moderately acid, so lime is usually a necessary soil
addition.
WHERE If an area gets less than 50% open sunlight or less
than 4 hours of sunlight per day, it is considered shady and tree
root competition is too great for turfgrass to grow well. High
mowing is essential in shady areas.
WHAT height you mow. Fescue grasses will not tolerate
close mowing. Mow high and often. Fescue should be cut no
shorter than 3" high. The higher you cut, the deeper your root
system is likely to be. Low cutting causes grass to develop a
shallow root system which makes the grass more susceptible to
disease and less able to survive our hot dry summers. Observe
the "1/3 Rule": never remove more than 1/3 of the grass blade.
Letting a lawn grow too tall before cutting is equally
detrimental. Unless grass has grown excessively tall, do not
pick up grass clippings. The light layer of clippings will
discourage weed germination, help preserve soil moisture, and
return organic matter to the soil. A sharp lawn mower blade
decreases damage to the grass blades, allowing them to heal
faster with less water loss. High mowing is even more important
for grass grown in shady areas. Never cut grass when it is wet.
You compact the soil and may spread diseases.
WHEN you fertilize. Do not apply fertilizer when grass is
wet. Use these three holidays to remember when to fertilize your
fescue lawn: Valentine's Day, Labor Day, Thanksgiving
Day.
Fertilizer: The recommendations made above are the easiest
for busy homeowners to manage but other types may be used.
Slow-release fertilizers may be used for one or both of the Fall
applications but they should not be used for the February
application. As long as you provide 1 lb. of actual Nitrogen
per
1000 sf at each fall application, and 1/2 lb. actual
Nitrogen in February, your lawn should do well. In spring,
excessive or late fertilization can predispose fescue to Brown
Patch.
Liquid vs granular fertilizer: liquid is more expensive
and requires more frequent applications but is quite satisfactory
if you are willing to do the extra work. Granular forms are
released slower than liquids.
HOW you prepared the soil. In heavy clay soils,
rototilling 6-8" deep is the key to success. Unless the
entire
potential root zone is uniformly limed and fertilized, the roots
of the grass will never occupy this soil zone, and the grass will
be less likely to survive stress periods in hot dry summers.
Compacted clay soils have severely depleted oxygen levels and no
plant can live without oxygen, so breaking up the soil allows
your plants to "breathe." Since some nutrients move minimally in
the soil, this is your only chance to get them into the root
zone. If feasible, incorporating some organic matter into the
soil will be beneficial. Your extra efforts now will pay
dividends for years in the future.
When to renovate and when to start over: If your lawn is
50% weeds or more, it is best to start over. All lawns must be
renovated eventually, but if it is less than 5 years since the
lawn was established, try to find out the reason for your turf
loss. The usual causes are:
Determine the cause or causes for the original failure and
correct them before trying to start over.
Recommended Varieties: The recommended combination is 5
lb. of a turf-type Tall Fescue (Bonanza, Lancer, Mini-mustang,
Phoenix, Rebel 3D, Safari, Taurus, Tomahawk, Virtue) plus 1/2 lb.
of each of two varieties of Kentucky Bluegrass (A34, Aspen,
Parade, Monopoly, Bristol, Ram I, and Wabash. Of these, A34, Ram
1, and Bristol are shade tolerant.) Most garden centers carry
seed with some of these varieties already mixed at approximately
this ratio. These amounts are for 1000 sf, or half the rate
for reseeding over existing turf.
Establishing a new lawn:
The best time to start a new lawn is September, since
germination and root growth of cool season grasses occurs only
when temperatures are somewhere between 60 and 80 degrees. Some
planning may be necessary so that you are ready to plant seeds at
the optimum time. An early start is especially necessary if
falling leaves from nearby trees are likely to smother young
seedlings when leaf-drop starts. Any time from August 15th on,
kill all existing weeds and grass. Skip one mowing, and irrigate
the area well 3 days in advance so that the grass and weeds are
actively growing and will absorb the herbicide. Spray area
thoroughly with a non-selective herbicide such as Roundup or
Kleenup. Wait 7 days and re-spray if any weeds reappear.
Prepare the soil as described above. Rake to level and leave the
soil as smooth as possible. Somewhat less effective but better
than nothing is the use of an aerator or verticutter to break up
the soil. Last choice is a vigorous hand raking. Seed at rate
of 6 lb. per 1000 sf. Excessive seeding should be avoided.
Rake lightly to achieve good seed-soil contact. Roll with a
light roller or tamp with a board to firm soil around the seed.
Cover sparsely with weed-free straw at rate of 1-2 bales per 1000
sf. Half of the soil should be visible through the straw.
Water: Keep the top 1/2" of soil moist. This may
require light waterings two or three times a day for 15-20 days.
If new seedlings are allowed to dry out, they will die. As the
seedlings grow and root, water less often but for longer periods,
so that the water penetrates to the root zone. Germination of
tall fescue usually takes from 12 to 14 days; bluegrass takes at
least 21 days, so do not stop watering at the first sign of
green. Mow when grass reaches 4 1/2", cutting no lower
than 3 ".
Renovating a lawn: Distribute evenly any lime and/or
fertilizer recommended by soil test. Aeration or verticutting is
desirable to loosen soil. Or rake very vigorously, scratching
soil to permit necessary seed-soil contact. Remove any excess
vegetation. Distribute seeds, and roll to
tamp seed into soil. Soak soil to depth of 6". You may
have to
do this in several stages. (See section on Watering).
Thereafter keep soil surface moist until grass is well
established.
Overseeding: should not be done routinely, but only when
there's an indication of need to do so. If a lawn is properly
established and proper management practices followed, there
should be no need for annual overseeding. Fescue is a bunch
grass which needs room to grow; overcrowding encourages diseases.
Use 1/2 the recommended rate when overseeding.
Temporary Lawns: When seeding "out of season," annual
ryegrass is suggested as a quick solution to avoid erosion.
Neither annual nor perennial ryegrass will survive the heat of
our summers.
While in
some years it is possible to seed lawns up until October, earlier
is desirable, particularly if you have trees which are likely to
drop leaves on young seedlings. Raking leaves may pull out
tender seedlings and unraked leaves may smother the young plants.
Past early October, chances of success diminish by the day.
Spring seeding: When spring seeding is necessary, weather
permitting, it should be done around February 15 but before
March, with the knowledge that the survival rate will be about
50%. Since root growth stops when the temperatures are high,
spring seeded lawns do not have enough cool weather to develop
sufficient root systems to allow them to withstand the heat and
drought of summer. You will probably have to do some reseeding
the following fall.
Watering: Fall is the driest time of the year in
Cumberland County,
so pay careful attention to newly seeded lawns. In summer,
fescue naturally goes semi-dormant (tops brown) during extremes
of hot and/or dry weather conditions; it can survive 3 weeks
without water. Water only when grass shows sign of wilt
(footprints will show when grass is walked on). Since grass
blades cannot absorb water, you must water deeply enough to reach
the root zone, 4-6". Water to the point of runoff, turn
off
sprinkler to let water soak in, then water again. Repeat until
root zone is wet. Unless the water reaches the roots where it is
taken up by the plant, you waste both time and water. Light
sprinklings on established lawns actually do harm by encouraging
shallow root growth. The best time to water is in the early
morning or late at night; late afternoon/early evening is the
least desirable as grass stays wet for a longer time, encouraging
diseases.
Liming: Liming may be done at any time of the year; it
takes several months for lime to change the pH of soil. Use
Dolomitic lime because it contains magnesium as well as calcium.
Either the pelletized form or the ground (powder) form may be
used. Aerating your lawn at the time of application will
increase movement of the lime into the soil. Even though
incorporation down to the root zone is most desirable, it is a
worthwhile practice to apply lime to the surface of an
established lawn when a soil test recommends doing so. If a
recommendation for more than 50-60 lbs. per 1000 sf is made,
divide the amount and make two applications, at least a month
apart. Once pH is corrected, liming is usually necessary every
2-3 years.
Moss is the result of:
The moss is present because growing conditions for fescue are
unsatisfactory. You can get rid of it temporarily with lime,
copper sulfate, aluminum sulfate, or several commercial products,
but unless the underlying cause is eliminated, the moss will
return.
Brown Patch is the most common and most serious disease of
fescue. The causative fungus is always present in turf but in
hot, humid weather it begins growing. Symptoms: small tan-brown
patches develop, gradually enlarging, and additional patches
appear as the summer progresses, some reaching 4-6' wide.
The
disease is more likely to appear if you have:
Weed Control: A severe weed problem often indicates a
low soil pH. Have your soil
tested.
Post-emergent: Controlling broadleaf weeds after they have
emerged is not a simple matter, and best control will be achieved
by identifying the specific weeds. There are wide-spectrum
herbicides for controlling broadleaf weeds (such as the mixtures
of 2,4-D, MCPP and dicamba which are sold under many brand
names), but you must read the label carefully and observe listed
precautions. Some herbicides have a soil residual and cannot be
used where runoff might reach desirable ornamental plants.
Post-emergent herbicides may be applied at any time that the
target weed is actively growing, but the application must be done
4-6 weeks prior to any seeding. Perennial weeds such as wild
garlic and dandelions must be sprayed in both growing seasons,
spring and fall.
Pre-emergent: Preventing germination of some summer
annual broadleaf weeds plus some grassy weeds (crabgrass,
goosegrass, etc.) is possible by using a pre-emergent herbicide
("crabgrass preventer," dacthal, etc.). Proper timing of the
application is essential if it is to be effective. For summer
annual weeds and grasses, apply the pre-emergence materials in
early spring, after forsythia blooms but before dogwood blooms.
To prevent germination of winter annual weeds, apply the
pre-emergent herbicide again in late August. If you intend to
overseed in the spring, you may use Siduron (Tupersan) for
control of selected weedy grasses like crabgrass. For fall
seeding, read and observe the label directions on herbicide
containers. Many have a waiting period before you may seed.
Newly planted lawns: Most herbicides have a waiting
period before they can be used after seeding, usually after
several mowings, so read each label carefully. Siduron
(Tupersan) and bromoxynil (Buctril) may be used selectively on
newly-seeded turf, but you must check the label before using
them.
Weed Killer/Fertilizer Mixtures: Proper timing of the
application of fertilizer and of herbicides is very important.
Unless each is applied at its correct time, results may be either
harmful or ineffective. Some weed-and-feed mixtures contain
pre-emergent herbicides to prevent germination of crabgrass and
other grassy weeds. Others are formulated to control broadleaf
weeds. The active ingredients are different, and the weeds they
control are different. Since the optimal times for fertilization
and for weed control often do not coincide, these mixtures are
not generally recommended. Correct cultural practices and
observing proper mowing height will help discourage weeds.
Bermudagrass in Fescue Lawns: There is no herbicide that
will kill Bermudagrass growing in a fescue lawn. All herbicides
that kill one will also kill the other. If the invasion is
severe, there is no alternative but to wait until August, treat
the entire lawn with a non-selective herbicide to kill both
grasses, and reseed in mid-September. Be sure to read the label
to observe the waiting period before reseeding.
A Final Tip: Pay at least as much attention to the roots
as you do to the grass and you'll have a healthy, attractive
lawn.
Feb. 15 5
lb. 10-10-10 per 1000 sf. (1/2
rate) Sept. 15 10 lb.
10-10-10 per 1000 sf.
Nov. 15 10 lb.
10-10-10 per 1000 sf. the
crucial one!
Fungicides
are available (Bayleton or Daconil 2787) but treatment becomes
economically un-feasible since spraying must be done every 2
weeks for as long as conditions remain favorable for development
of the fungus. Walking on or mowing wet grass can spread Brown
Patch. Have soil tested to correct any nutrient deficiencies and
observe proper management practices to help avoid the disease.
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