Soil preparation for a lawn
To determine any soil deficiencies and to optimize soil for
growing turf, obtain a soil test. Penn State Soil Test Kits make
the job simple. The kits can be found at many local nurseries or
by following the instructions at the end of this article. Test
results are available within 7-10 days.
Using a spade, strip the existing vegetation, shaking off as
much topsoil as possible that clings to the roots.
Alternatively, apply an herbicide as directed by the
Rototill or hand-dig the soil to a depth of 4-6 inches. Don’t
overdo the rototilling; the goal is to end up with soil pieces,
Remove rocks, stones, vegetation and other debris.
Add the recommended soil amendments at the rate prescribed by
the soil test. One or 2 inches of quality compost can also be
added. Quality compost is well-aged and of neutral pH. Reputable
landscape supply companies can provide this information about
their products. Work the amendments and compost into the
rototilled soil and level with a rake.
The re-worked soil should be watered well. Allow the soil to
settle for several days, then move on to the planting phase.
Planting the Lawn
Select grass seed. Using seed is economical and it also allows
customization of the type of turf comprising the new lawn.
Grasses in our region are considered “cool season” because they
do most of their growing in spring and fall. A good grass seed
mixture should consist of 40-60 percent Kentucky bluegrass,
30-40 percent fine fescues and 10-20 percent perennial ryegrass.
It is vitally important that you source the freshest seed
available. Nurseries can provide that information if they are
selling their seed in bulk. If you are purchasing a pre-packaged
seed, expiration dates are noted on the label.
Using a drop spreader, spread the seed according to the
suggested rate on the seed package. If desired, the seed can be
divided in half. Spread half the seed in one direction, then
spread the other half at a right angle relative to the first
Lightly go over the soil with the back side of a rake to cover
the seed with about ¼-inch of soil.
Add a light layer of mulch such as straw or compost to help
moderate temperatures and prevent moisture loss. If straw is
used, it should not completely cover the soil surface, but
rather, form a “netting” so that sunlight can reach the soil. Do
not use hay as a mulch because it contains many weed seeds.
From this point on, as the seeds start to germinate, keep the
soil evenly moist, but not constantly wet. Don’t allow the soil
to dry out or the grass seedlings will die.
Observe the fuzzy sprouts of grass as the seeds germinate. When
the grass reaches a height of about 3 inches, it is time to mow.
Carefully remove straw mulch before mowing. Using a mower with a
sharp blade, cut the grass to a height of 2 inches. A
sharp blade is crucial in cleanly cutting the tender young grass
without damaging the plant tissue.
Continue cutting weekly, removing 13 of the grass height, until
the grass goes dormant in late fall. Dormancy occurs as the
nighttime temperatures continue to fall close to freezing and
the grass’ rate of growth diminishes.
Starting next spring, and beyond, additional over-seeding and
selected amendment additions may be needed to maintain a thick,
weed-free, healthy lawn.
Help from Penn State
Penn State Soil Test Kits can be obtained directly from the
Allegheny County Extension office at: Penn State Center
Pittsburgh, Energy Innovation Center, Suite A; 1435 Bedford
Ave., Pittsburgh, PA 15219.
For more information including pricing, office hours and
obtaining a soil test kit by mail, call 412-263-1000. For practical how-to information on gardening and more, visit:
Fall gardening tasks
Sedums are perfect for
late summer weather