The long, hard winter has made life so tough for
your lawn that a normal,
helpful practice may not be such a good idea now.
Normally, late-winter dethatching of dormant
turf is a good idea. But
normal winters aren’t as harsh as the one your lawn has just
endured.
"We had some pretty cold weather this
winter," said Gil Landry,
a turf specialist with the University of Georgia Extension
Service. "Because of that,
you might want to hold off on your normal dethatching while your
grass is still dormant.
"It would be safer to wait until after the
turf greens up and is
growing well," he said, "but before the hot, dry
weather of July and
August."
Be sure to keep the root zone moist during
spring green-up, too, Landry
said.
"Apply at least one-quarter inch per week
until 50 percent green-up,
and then go up to one-half inch per week," he said.
"Water at this time can
literally save your grass.
"Just like you," he said, "our
grass needs water to be
healthy. A little water now can get your grass off to a good
start for the rest of the
season."
Dethatching is still important for your lawn,
though. Thatch is a buildup
of dead grass stems and other plant matter between the grass and
the soil.
If thatch gets more than a half-inch thick, you
need to do something about
it.
"If it gets that thick," Landry said,
"most of the grass
root system is growing in the thatch, not in the soil."
That can lead to all kinds of problems for the
lawn. Thatch freezes faster
than the soil. That can make winterkill worse when hard freezes
come.
Thatch dries out faster than soil, too, so the
lawn will be stressed more
by summer drought stretches.
"Thatch is also a good environment for
insects and disease organisms
that can injure the grass," Landry said.
You may have a thatch problem, he said,
"particularly if you have
centipede grass, if the lawn is really spongy and soft when you
walk across it."
Dig your fingers into the sod, grip the grass
and try to move it around.
If the grass moves, you have too much thatch. "You
shouldn’t be able to move it at
all," he said.
How do you get rid of thatch?
Most people use a vertical mower or some
attachment to a lawn mower. You
probably don’t have a vertical mower, but most towns have rental
places that carry them.
"On centipede or St. Augustine, the
vertical mower blades need to be
two to three inches apart," Landry said. "Blades
closer than that would remove
too much turf and increase the recovery time for the grass. And
you should go across the
lawn only one time.
"With Bermuda or zoysia grass the blades
can be closer
together," he said. "And you can go across the lawn
more than once."
Don’t try to get rid of all that thatch at
once.
"Do it gradually," Landry said,
"to prevent too much damage
to the turf."
The best way to handle a thatch problem, though,
is to prevent it.
"You can do that by mowing your grass at
the proper height,"
Landry said. "Mow it often enough that you remove only a
third of the total
height."
You get a bonus if you mow the grass on a good
schedule, he said.
Besides keeping thatch from building up, you
don’t have to remove grass
clippings. And that allows you to recycle your costly fertilizer
all summer.
