Q. I started a new lawn last fall and I am very happy
with the results. I want to re-seed the
areas that came up a bit thin. When and how should I do that so I don’t damage
the rest of it? I was also considering doing an aeration soon, as I always did
every winter at my previous home with great results. Should I aerate this
younger lawn?
with the results. I want to re-seed the
areas that came up a bit thin. When and how should I do that so I don’t damage
the rest of it? I was also considering doing an aeration soon, as I always did
every winter at my previous home with great results. Should I aerate this
younger lawn?
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| It is common for newly seeded lawns to be a bit “thin” at first, but larger open areas should be reseeded. |
A. I understand your concern about the lawn being too
thin but this can oftentimes be the case in a new lawn, particularly with cool
season grasses like fescues. Fescues fill in voids between seedlings primarily by
“tillering”.
thin but this can oftentimes be the case in a new lawn, particularly with cool
season grasses like fescues. Fescues fill in voids between seedlings primarily by
“tillering”.
They do
not have the capacity to fill voids with strong rhizomes (underground stems)
and stolons (above ground stems that lay on the soil surface). Frequently these
are more associated with the warm season grasses such as bermudagrass, zoysia
and St. Augustine.
not have the capacity to fill voids with strong rhizomes (underground stems)
and stolons (above ground stems that lay on the soil surface). Frequently these
are more associated with the warm season grasses such as bermudagrass, zoysia
and St. Augustine.
Tillering
is the “sprouting” of side shoots from the base of the plant. As a
grass plant emerges from the seed it shoots up one stem with associated leaf (‘mono’
‘cotyledon’ or one leaf). This single stem with one leaf that eventually
sprouts side leaves along the stem will grow very tall before it sends up side
shoots unless the tip of this single stem is cut off. This is done by mowing
(prior to lawn mowers it was done by animals eating the grass or grazing).
is the “sprouting” of side shoots from the base of the plant. As a
grass plant emerges from the seed it shoots up one stem with associated leaf (‘mono’
‘cotyledon’ or one leaf). This single stem with one leaf that eventually
sprouts side leaves along the stem will grow very tall before it sends up side
shoots unless the tip of this single stem is cut off. This is done by mowing
(prior to lawn mowers it was done by animals eating the grass or grazing).
Once the
single stem has been cut off, the plant kicks into a survival mechanism and
sends up side shoots (tillers) around the central single shoot. The side shoots
occupy space around the central shoot and begin to fill in the voids between
germinating seeds.
single stem has been cut off, the plant kicks into a survival mechanism and
sends up side shoots (tillers) around the central single shoot. The side shoots
occupy space around the central shoot and begin to fill in the voids between
germinating seeds.
 |
| Tillers are side shoots that come from the base of the grass plant such as this Poa annua bunchgrass. |
It is
very natural to have these voids or open spaces around the seedlings for quite
a long time unless we “graze” on the plants with our lawn mowers. So
just by cutting or mowing the lawn we will encourage the lawn to get thicker by
individual grasses “tillering”.
very natural to have these voids or open spaces around the seedlings for quite
a long time unless we “graze” on the plants with our lawn mowers. So
just by cutting or mowing the lawn we will encourage the lawn to get thicker by
individual grasses “tillering”.
This is
further sped up with a little bit of nitrogen fertilizer applied every few
weeks, warm temperatures and regular waterings.
further sped up with a little bit of nitrogen fertilizer applied every few
weeks, warm temperatures and regular waterings.
Most
lawn weed seeds respond to sunlight (they germinate when they “see”
light). So quickly filling the spaces between grasses by tillering helps to
reduce weed invasion in new lawns.
lawn weed seeds respond to sunlight (they germinate when they “see”
light). So quickly filling the spaces between grasses by tillering helps to
reduce weed invasion in new lawns.
Weed seeds
like to germinate when soil temperatures hit about 50 to 55 F which would be in
early to mid-February or perhaps sooner in real warm microclimates. So it is
important to get the grass up and shade the soil surface as soon as possible in
the spring.
like to germinate when soil temperatures hit about 50 to 55 F which would be in
early to mid-February or perhaps sooner in real warm microclimates. So it is
important to get the grass up and shade the soil surface as soon as possible in
the spring.
In fact,
I prefer fall lawn seeding because of weed problems and fall and the following
spring weather gives the seed a double dose of good weather for establishment.
I prefer fall lawn seeding because of weed problems and fall and the following
spring weather gives the seed a double dose of good weather for establishment.
However,
if you feel the distance is still too far apart between these seedlings then I
would use the exact same seed and lightly seed in these areas and lightly cover
the seeds with topdressing.
if you feel the distance is still too far apart between these seedlings then I
would use the exact same seed and lightly seed in these areas and lightly cover
the seeds with topdressing.
If you
want faster germination, soak the seed in cool water for several hours (not
overnight or you will kill them) and then dry them long enough to dry their
surface so they can be spread easily.
want faster germination, soak the seed in cool water for several hours (not
overnight or you will kill them) and then dry them long enough to dry their
surface so they can be spread easily.
Do not
dry the entire seed out or you will kill the seed. Once they are surface dry
you can spread the seed and you will save yourself a day or two of germination
time. Fertilize lightly every couple of weeks and mow as soon as you can cut
off 1/4 of the length of grass. Do not pick up the clippings but let them
compost back into the soil unless it is loaded with weeds.
dry the entire seed out or you will kill the seed. Once they are surface dry
you can spread the seed and you will save yourself a day or two of germination
time. Fertilize lightly every couple of weeks and mow as soon as you can cut
off 1/4 of the length of grass. Do not pick up the clippings but let them
compost back into the soil unless it is loaded with weeds.
How much yield should one expect from a quarter?
I’m sure it varies to the strain but ballpark figure.
I'm not sure what you mean by a "quarter" and a "yield". I reread the post figuring I said something wrong but didn't see it.