Watering
Your Lawn
SPRING
ESTABLISHED
LAWNS
Give the lawn a good
soaking. Leave the sprinkler in each spot for 1 1/2 to 2 hours* once a
week. In unusually warm weather, it may be necessary to water more
often.
NEWLY
SEEDED AREAS
Leave your sprinkler in
each spot 20- 30 minutes,* daily if necessary, to keep the top inch of
soil consistently moist for 4 weeks. Then water 45- 60 minutes,* 2- 4
times a week for the next 4- 6 weeks.
LAWNS
THAT ARE PARTIALLY ESTABLISHED FROM FALL SEEDING
Leave your sprinkler in each spot 45-
60 minutes,* 2- 4 times a week. The intent is to moisten the soil more
deeply to facilitate deeper rooting as the seeding mature. Keep spot
seeded areas consistently moist for 4- 5 weeks.
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Give the lawn a good
soaking. Leave the sprinkler in each spot 1 1/2 to 2 hours once a week.
In unusually warm weather, it may be necessary to water in this fashion
2 to 3 times a week.
HOT
SPOTS AND EXPOSED AREAS
Areas that tend to dry out quickly need
water more often than the rest of the lawn. While most of the lawn needs
only one good soaking each week (see above), hot spots may need water 2
or 3 times a week. This is especially true during hot, dry periods
throughout the summer.
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SUMMER
ESTABLISHED
AREAS
Give the lawn a good
soaking. Leave the sprinkler in each spot for 1 1/2 to 2 hours once a
week. In unusually warm weather, It may be necessary to to water in this
fashion 2 or 3 times a week.
HOT
SPOTS AND EXPOSED AREAS
Areas that tend to dry out
quickly need water more often than the rest of the lawn. While most of
the lawn needs only a good soaking each week (see above), hot spots may
need water 2 or 3 times a week.
RECUPERATIVE
WATERING
If the lawn goes without watering for
an extended period during the summer, It may undergo severe drought and
temperature stress. The lawn may become brown as the grassplant
sacrifices leaf. To revive the lawn, it is necessary to water the lawn 2
or 3 times a week (every other day) for 1 hour or more in each spot. You
may need to water in this fashion for 2 weeks or until the lawn grows
out again.
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GRUBS
White grubs are the immature (or
larval) stage of a dozen or more different beetles, e.g., Japanese
beetle, May or June beetles, and others. They are fat, 'C' or 'U'
shaped, worm-like, and are found in the soil just brown head, a dark
area at the posterior end of the body (the raster) and three
 pairs
of legs close to the head. White grubs hatch from eggs laid in lawn
areas by the adult beetles in mid- to late-summer. The eggs hatch and
soon the grubs begin feeding on the roots of the turf grass in
late-summer and fall. Once the soil temperatures drop in the late-fall
and winter, the grubs burrow 6-10 inches below the soil surface and
hibernate over the winter. Once the soil temperatures warm up in the
spring, they return to the turf's rootzone and begin feeding
again. The grubs have only a short feeding period in the spring before
they enter their pupae stage in the late-spring or early-summer. Due to
the short feeding period and increased root development by the
grassplants during the spring, lawn damage is usually outpaced by lawn
growth. During pupation the grub's body is transformed into the adult
beetle form. The adult beetles emerge from the lawns in early- to
mid-summer and feed on foliage of many plants. The adult beetles mate
and lay eggs in the mid-summer and the cycle begins anew.
The damage caused to lawns by
grubs during the late-summer/fall can reach catastrophic proportions.
The insects prune off most of the underground roots, making the plant
incapable of acquiring water or nutrients for life support. The grass
wilts and dies in large, irregular brown patches. The dead areas and
adjacent sod can be rolled back like a carpet, usually exposing the
grubs below.
Control of white grubs in lawns can be
difficult to achieve. Insecticides used to control them tend to bind
with the thatch layer. This can reduce the penetration of insecticides
intended to directly contact them. Due to their fast evolutionary cycle,
grubs develop immunities to insecticides relatively quickly.
Consequently, control products may have a limited life span. The best
time to apply insecticides for control of grubs is when they are young
and actively feeding, i.e., in the late-summer/early fall. In addition
to proper application timing, adequate soil moisture is critical to
achieve control. Heavy watering (1-2 hours each area) soon after the
application is imperative to successful control.
There are a number of perennial grass plants that can become
objectionable once established in a home lawn. In general, these types
of plants cannot be selectively controlled; that is, they cannot be
killed without also killing adjacent and intermingled desirable turf
grasses. There are warm-season and cool-season perennial grasses that
may become a "weed" problem. The warm-season grasses include
common Bermuda grass (sometimes called "wiregrass"), improved
Bermuda grasses, nimblewill, and Zoysia grass. Cool-season perennial
problem grasses include Bentgrass, common Ryegrass, Orchard grass,
miscellaneous coarse-bladed Fescues, several other types of
coarse-bladed grasses, and sometimes fine-bladed Fescues.
These problem plants become established
in lawns as they age through a variety of means. Most volunteer into the
lawn. Zoysia and improved Bermuda grasses usually have been established
deliberately. Once established, undesirable species can be masked,
eradicated, or ignored. Masking usually involves over seeding with
larger, coarser-bladed, but desirable turf grass types fescue. This
approach is not appropriate in a lot of cases.
Eradication involves
the application of a nonselective herbicide to areas infested with the
undesirable grass(es). This type of herbicide will kill both undesirable
and desirable grasses in areas sprayed. Multiple sprayings are generally
required. Once all of the grass is dead, the area may be re-established
by seeding with desirable species of turf grasses. The areas
deliberately killed may need to be dethatched prior to the reseeding.
This entire process is usually referred to as "renovation".
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 There
are a number of fungus diseases that affect turf grasses grown in our area.
Most are more cosmetic nuisances than lawn killers, though there
are a few that can devastate a lawn in short order if left unchecked.
Fungus diseases are a fact of life in lawn care in Northern Virginia.
Virtually every lawn has some disease problem during the growing season.
Most lawn diseases can be controlled with varying
 degrees
of success, but there are some that
can't be controlled at all. Fungus diseases can be generally
classified according to when their symptoms appear, as cool-season and
warm-season diseases. However, there is a lot of overlap in seasons
during which specific disease pathogens are
active. The cool-season diseases
include Snow
Molds, Red Thread, Leaf Spot, Smuts, and Rusts. Warm-season diseases
include Dollar Spot, Brown Patch,
Summer Patch,
Necrotic Ring Spot, Pythium
Blight, and Meltout.
 There
are complex interrelating factors involved that can lead to the
emergence of disease. Some of them are grass type, soil type, soil
fertility level, soil acidity level, soil moisture levels, humidity,
soil and air temperature levels, amount of thatch, mowing habits, and
other factors as well. In general, fungus diseases are symptoms of some
underlying problem. In most of the disease problems Agro-Lawn treats,
the underlying problems are too little water, too much water,
 too
high temperatures, excessive thatch, and acid soil. Lawn disease is not
something about which the lawn owner should get to upset. Diseases come
and go. If damage cannot be avoided, it can always be repaired via
seeding and conditions can be altered to reduce the degree or frequency
of the problem in the future.
The client can help to minimize
fungus problems by following these general instructions: 1) Cut high
with a sharp blade at proper intervals, 2) Water properly when the lawn
needs it, 3) Don't water in the evening, 4) Allow the lawn to dry out
between watering. More detailed information can be found in the
instructions left at the time of each service. Maintenance of thatch
accumulation, preferably by core aeration, and maintenance of proper
soil pH through periodic lime applications is important. Despite the
best of care, lawns will get disease problems from time to time.
Fungus diseases are
primarily dealt with on a curative basis. When Agro-Lawn treats a lawn
for a disease problem, we are trying to arrest the spread of the
disease. There is usually lawn damage that has occurred prior to the
treatment. Since most serious disease problems occur during the summer,
it should be understood that where the grass has actually died, it will
not repair at that time. During most summers, the grass is not usually
actively growing; it's just trying to survive. Repair will occur during
the following fall. Seeding may be necessary. Depending upon the disease
in question, it may be necessary to reapply fungicide after a couple of
weeks if the symptoms persist. It is not desirable to apply fungicide
too frequently. Fungus pathogens will become immune to the fungicides
with too much exposure; then there may not be a means of control.
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Thatch Control
As lawns develop and age, a layer
of primarily dead, undecayed root and stem tissue will accumulate at the
soil surface. This layer is called “thatch”. Some types
of grasses produce more than others. In general, the denser and
faster growing a lawn is, the more thatch accumulates. Mowing
controls the quantity of leaf tissue a grass plant generates.
Grass leaves are quickly decomposed by soil organisms, but the root and
stem material in thatch is not. A limited amount of thatch is
desirable to insulate the grass plants from temperature extremes, but
excessive thatch will cause problems. Too much thatch also
interferes with the passage into the root zone of water, air and applied
nutrients. If all of these things necessary to plant growth are
available in the thatch rather than the soil, the grass begins to root
in the thatch. When this occurs, the grass is very susceptible to
damage from temperature extremes and drought. Too much thatch also
increases the likelihood of damage from disease and insect
feeding. Without some provision for thatch control, lawn quality
may decline as the lawn ages. The most cost effective and least
lawn damaging means of controlling thatch accumulation is coring
aeration. Thatch may also be removed mechanically, but this is
both expensive and disruptive to the lawn.
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Coring Aeration
Coring aeration involves the removal of
thousands of “cores”, or plugs about the size of your index finger
from the lawn at roughly 4 – 6 inch centers. Coring aeration increases
the rate of thatch decomposition by greatly increasing the surface area
of thatch accessible to soil microbes. After a lawn is core
aerated, soil microbes can attack thatch not only at the soil surface,
but also inside each of the many coring holes. In addition to
increasing the rate of thatch breakdown, coring permits easier passage
of water, air, and applied nutrients into the lawn’s root zone.
Coring also relieves soil compaction, further enhancing root
development. Coring aeration is extremely beneficial to
lawns. In general, Agro-Lawn personnel will recommend that lawns
be cored at least annually, although there are some situations where
coring is not advisable. The best results from coring aeration can
be expected in April, May, June September and October.
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Dethatching
“Dethatching” refers to the
removal of thatch material from a lawn. Dethatching should not be
confused with “power raking”. Power raking involves the use of
a machine to rake across the surface of the lawn removing a lot of dead
grass leaf material, but very little actual thatch. Performing power
raking, or giving the lawn a good, stiff hand raking in the early spring
is an excellent practice. It removes dead leaves and debris,
improves air passage around the grass blades and stimulates new
growth. Your lawn would benefit from power raking annually, and we
highly recommend it.
True dethatching however is labor
intensive, expensive and very disruptive to lawn quality.
Consequently, Agro-Lawn does not usually recommend dethatching except
when a lawn is already significantly damaged. The purpose of
dethatching at this point is not to control the thatch, but to prepare
the lawn for reseeding. In most instances, this requires the
removal of all debris to bare the soil for the best seeding
results. This type of dethatching is called “renovation”
dethatching. Powered equipment is used to vertically cut through the
thatch and lift it to the surface. This generates a large amount
of debris which is then either raked up and bagged for disposal, or
deposited on the customer’s property at an area designated by him.
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