The time to start or re-seed a cool season lawn is in the fall. You need good seed-to-soil contact and sunlight to spark seed germination
and turf growth. If you have weeds in your yard, try a weed killer before overseeding. This can increase your chance of success
with the new grass seed. Timing is important. Check your labels to see how long to wait from using a weed killer and spreading
new seed.
time) to start or re-seed cool season lawn
grasses on the Cumberland Plateau. Trying
to establish a lawn from seed in spring
or summer and/or overseeding mature
turfgrass during those seasons is rarely
successful here.
Good seed-to-soil contact is very
important. Sunlight also is important to
good seed germination and turf growth.
With an established but weedy lawn, I
would use a weed killer before overseeding.
By eliminating weeds 2-3 weeks
before sowing seed the chance of success
is increased. More grass seeds will fall
to the ground rather than getting caught
on the weed plants and the weeds won’t
be there to shade the soil. I’d also cut the
existing turfgrass short just prior to overseeding.
Timing is important. Broadleaf weed
killers that are fatal to weeds like dandelions
yet don’t harm mature turfgrasses
can injure young grass plants. Grass
from a spring overseeding will not be hurt
by such herbicides applied in September.
However, with a reversed fall schedule
– first overseeding followed by an
application of broadleaf weed killer just
weeks later — the new turfgrass may suffer
harm.
Examples of products for homeowner
use that kill weeds but not the grass are
Ortho brand WEED B GONE or Spectracide
brand WEED STOP FOR LAWNS.
Check the label on the product you choose
to verify the wait-time between application
of weed killer and safe reseeding and
also to learn which weeds the product is
formulated to eliminate. Fact sheets on
weeds and methods to eliminate them are
available at the University of Tennessee
website www.tennesseeturfgrassweeds.org
for download to your home computer.
While climate change has brought more
rainfall to our part of Tennessee in recent
decades, we also experience sunny, dry
periods with high temperatures that cause
turfgrass stress. I chose improved fescue
blends for my yard because KY bluegrass
needs more water to combat drought stress
and I don’t irrigate my turf. Kentucky 31
is an old fescue blend that I don’t recommend.
Using blends that mix rye grass in
with KY bluegrass or fescue seed is not
recommended by UT. The website extension.tennessee.edu/publications
also has
information on lawns and various turfgrasses.
The publication “Turfgrass Establishment:
Turfgrass Seed” gives more
details on different varieties and seeds.
22 | Cumberland Now • September 2020