Ideal Time for Lawn Renovation
Early fall is an ideal time for renovating lawns in northern Illinois.
Renovation can involve a variety of lawn care practices, depending
largely on the condition of the lawn and underlying soil conditions.
Many lawn problems originate from poor soil conditions, such as
heavy clay, compaction, and poor drainage. These situations should
be corrected during renovation.
On the other hand, many lawn problems tend to be due to pests,
weather conditions, or poor lawn care practices. Sometimes simply
improved mowing, fertilizing, and watering may be all that's required
to achieve acceptable lawn quality.
The lawn renovation process can be much easier if the proper equipment
is used. For example, core aerification is often suggested for lawn
care, especially for sodded lawns sitting on clay. This process
is very useful to help reduce soil compaction and thatch, improve
surface drainage, and improve conditions prior to overseeding. Core
aerifiers insert hollow tines into the lawn and pull out plugs of
soil. Size of cores removed will depend on the machine used, soil
moisture, and type of soil. Core spacing also varies with the specific
machine being used. Machines can be rented or aerifying services
are available for hire.
Vertical mowers are machines with rotating blades
arranged vertically that can cut into turf and soil. These machines
can be used to remove thatch, and are sometimes called dethatchers.
Turfgrass rooting in the thatch is typically torn out, so reseeding
is suggested afterwards. Vertical mowers can also roughen the soil
prior to overseeding areas.
Another very useful machine for renovation procedures is the slit-seeder,
which combines vertical mowing with seeding. As the machine goes
across the lawn, it opens the soil and deposits seed directly into
the soil opening. Most slit-seeders have a roller that helps firm
the soil after seeding. Seed is metered at a predetermined rate;
it's suggested to apply half the desired seeding rate in one direction
and the other half on a second pass perpendicular to the first.
Since the seed is placed in direct contact with the soil, seeding
success is usually high when using slit-seeders. In addition, existing
grass and debris does not need to be completely removed prior to
the overseeding process. Timing should be the same as for conventional
lawn seeding, which ideally would be late August into early September.
Many rental agencies carry slit-seeders or many lawn and landscape
services can do it for hire.
Once the problem has been identified, the renovation process may
begin. Renovation may be as simple as correcting basic care practices.
It may also just involve overseeding with little additional work.
Another option is allowing existing grass to remain but working
on reducing thatch and overseeding. The final option is completely
removing the existing lawn and starting over, which may be required
for poor lawns sitting on very poor soil conditions.
Base the decision of which option to choose on how much desirable
grass exists and the soil conditions. For example, if the lawn is
just a little thin, overseeding with a quality lawn seed in late
August or early September may be the answer. Use of a slit-seeder
is an ideal way to overseed lawns. Seed may also be broadcast over
thin lawn areas, but there needs to be good soil to seed contact.
Dethatchers or vertical mowers can also be used to tear out excess
debris prior to overseeding. In addition, slit-seeding could also
be done directly through grass and/or weeds killed with the nonselective
herbicide glyphosate. All of these types of overseeding procedures
do not require additional soil modification.
When soil problems exist under a lawn, there are ways to address
them without tearing up the lawn. As mentioned earlier, core aerifying
is suggested for problems such as thatch and soil compaction. Aerifying
and then overseeding or slit-seeding (breaks up cores) may be an
ideal level of renovation for many lawns.
Unfortunately, some lawn problems, such as soil problems of severe
compaction, high clay levels, or poor drainage, may require starting
over. Remove existing grass or rototil it. High populations of perennial
weed species may require use of a nonselective herbicide, such as
glyphosate. Thoroughly work the soil to a depth of 6 inches. Add
amendments such as compost, rotted manure, organic topsoil, peat,
etc. Follow proper selection and establishment procedures to get
the new lawn off to a good start.
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for Lawn Renovation