|
|
Lawn Dawg Red Alert:
Crabgrass Maintenance
|
|
|
Has Crabgrass got you
down?
Don't throw in the towel just yet. This has been an extraordinarily difficult summer
if you are trying to grow grass. Indeed,
if someone were looking at your yard they may think that you were trying to
grow crabgrass.
I'll tell you a secret. I haven't applied crabgrass control to my
home lawn in years, yet my crabgrass population is about 1 - 3 % tops. Why? Because I follow some simple rules that, when repeated religiously over
the course of many seasons, resulted in low weed seed populations in the soil. Notice how I worded that - low weed seed populations. There are not many crabgrass seeds in the
soil of my lawn.
The ancient Chinese military
strategist, Sun Tzu, has some advice for we crabgrass warriors, "Keep your friends close, and your
enemies closer." Crabgrass is the
enemy. If you are going to succeed at
controlling crabgrass, you have to understand it. |
Understanding your foe.
Crabgrass is a summer annual, meaning
that it completes its life cycle within a single season and is present
during the
summer months. It utilizes a different
form of photosynthesis than the turfgrasses we use in our lawns. That
means that when it gets hot and dry, our
turfgrasses go into dormancy until it becomes cooler and moister towards
the
fall, while crabgrass excels in the hot, dry and humid summer months. Mother nature has provided the crabgrass
plant with the definitive competitive edge over the turfgrasses we want
in our
lawns.
|
What's next?
This is what you can expect of crabgrass
for the remainder of the season. As we
head toward the end of August, the nighttime low temperatures will begin
to
plummet, signaling the beginning of the end for the crabgrass plants. Their rate of growth will slow dramatically;
their color will go from the brilliant yellow to a deeper green to a
reddish
green. Crabgrass will be killed by the
season's first frost.
A long-term solution.
When a crabgrass plant matures, it
produces hundreds of thousands of seeds that will drop to the soil
surface, overwinter,
and germinate the next spring or many springs in the future. Seeds can
lie dormant in the soil for many
years before germinating.
S o the first secret to controlling
crabgrass is to limit the number of seeds that existing plants produce. That is what we are doing right now with our
post-emergent crabgrass control applications. We cannot make the crabgrass plants we have now disappear, but we can
stunt their growth or kill them outright, thus limiting the number of
seeds
they produce.
Second, we start right now to control
crabgrass for next season. How? First we need to make the lawn as
healthy as
we can by encouraging a deep and vigorous root system to develop this
fall. Turfgrass plants will develop roots right up
until frost enters the soil - anywhere from mid-November to late December.
The late summer, early fall and late
fall fertilizer applications will go disproportionally towards
developing
roots, which will be used to supply the plants with water and
nourishment next
year. Remember, a
vigorous, healthy lawn is the best defense against weeds!
Your job this fall is to make sure that
the lawn is getting the proper amount of irrigation. Mother nature
usually provides plenty of
rainfall in the autumn, but if she does not (and your municipality
allows you
to water) you have to ensure the lawn gets it. Next, you have to fill in any bare areas on the lawn that have
developed. We can help with our
aerefication and overseeding service, or you can do the job yourself.
 Next, mowing is critical during the
fall. Be sure that your
mower's blade is sharp. A
dull blade injures the grass plant, opening it up to disease infestation
-
additional stress for the plant to overcome. Cut as tall as you can. The amount of plant mass above the ground is
roughly equivalent to the amount of plant mass below the ground. Don't
allow excessive clippings
to remain on the lawn. Either
mow more often so that you do not remove more than 1/3rd of the leaf
surface in
a single mowing, raise your cutting height, or wait until the dew has
dried
before cutting as the case may be.
Once autumn is in full swing, keep tree
leaves from becoming wet and matted on the lawn. This can be
accomplished by blowing the
leaves off the lawn or collecting your clipping while mowing. Leaves
that become wet and matted on the lawn
smother the grasses below them crating voids in the lawn, which are
perfect
places for crabgrass seeds to germinate.
And whatever you do, do not succumb to the
temptation to lower your mowing height as the lawn recovers from the
summer. Leave the short grass to the
golf courses. Keep the lawn
consistently cut at 2 ½ to 3" tall. Lawn Dawg has handy mowing height rulers. If you'd like one, please let
us know.
Next Season.
Next season, timing the first
application is critical. Be sure to
clear off and prepare the lawn for the first treatment as soon as you
can. Any aerefication or dethatching needs to be
performed before the preemergent crabgrass control is applied.
 A successful application of preemergent
crabgrass control should provide about 90% control of all crabgrass
seedlings
that germinate. So if 100,000 seeds
germinate in your lawn next spring we can expect to control 90,000
plants. Then there will be only 10,000 plants to
produce seeds for the next year - and the next year you can expect to
control
90% of those seeds, and so on and so on. What is happening is that you are depleting the number of
crabgrass seeds in the soil that are available to germinate in a given
year. That is why patience and persistence are
vital to a good lawn care program. One
application or even one whole season does not make a successful lawn
care
program.
Successful crabgrass control will
happen, but you have to be prepared for a long-term battle. If you do
your part with the mowing and
watering, and we do our part with the proper products applied at the
proper
time, we can get your crabgrass problem under control!
|
|
Share this Crabgrass Alert!
For more lawn care and tree and shrub care literature, check out the Lawn Dawg Blog!
|
|
|
|
|
|
|
