Crabgrass
Preventative
One
of the primary weed concerns in home lawns is crabgrass. There is
plenty of time before this weed will appear in lawns, but prevention
is the key to control. There are both cultural and chemical control
options to consider.
First, understand the target
weed. Crabgrass is a warm-season annual grass. No matter how many
crabgrass plants appeared in your lawn last year, they are all dead.
Crabgrass can only reappear in from germinating seeds. Crabgrass will
not start germinating until soil temperatures get close to 60 degrees
and stay there for several consecutive days, which most likely is
not until late May or early June in lawn areas. So remember, you have
plenty of time.
Crabgrass prefers full
sun, moisture, and thin lawns that allow light to hit the soil. Sound
lawn care practices to allow for thick, vigorous lawns that shade
the soil help prevent crabgrass from becoming a problem. Mowing height
perhaps has the most impact on crabgrass. Mow between 2 1/2 and 3
inches and there will be fewer crabgrass plants in your lawn.
In addition, avoid frequent
watering, especially frequent light sprinklings. If possible, hold
off lawn establishment or renovation work until late summer to avoid
potential crabgrass problems from appearing on open soil areas in
lawns.
Preemergence
herbicides (weed killers) are available to use in spring for crabgrass
control. These need to be applied to the lawn before crabgrass germinates.
Late April into early May is the suggested time for applying preemergence
crabgrass herbicide in our area. If April is unusually warm, apply
by late April, otherwise early May is not too late.
Most preemergence crabgrass
herbicides are found in combination with lawn fertilizers, so crabgrass
prevention and spring fertilization can be done at the same time.
Follow the rates given on the bag. One word of caution; except for
siduron, all preemergence herbicides for crabgrass will also damage
germinating desirable grass seed. Siduron may be found as lawn starter
fertilizer with crabgrass preventer.