Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: WEDNESDAY, September 20, 1995 TAG: 9509200009
SECTION: CURRENT PAGE: NRV-9 EDITION: NEW RIVER VALLEY
SOURCE: JOE HUNNINGS
DATELINE: LENGTH: Medium
Some conditions reduce the chances of successful renovation. If a lawn is extremely compacted, has a pH below 5.2, has very low soil phosphorus availability, or has a very uneven grade, complete re-establishment with plowing or disking may be a better choice.
Before renovating your lawn, you should determine the cause of poor quality. This will keep the lawn from succumbing to past problems.
Lawns usually require renovation for one or more of the following reasons: poor fertilization practices, inadequate drainage, excessive traffic, poor selection of grass variety, weed invasion, compaction, drought, insect or disease damage or excessive shade.
One of the first steps before planting is to have the soil tested. The soil analysis will determine lime and fertilizer needs. Ideally, the soil should be tested at least a month before the lawn renovation is started. The Soil Testing Laboratory at Virginia Tech will test your soil for $6 and will return your results in a little more than a week.
The next step is to control weeds and undesirable grasses. If possible, control perennial grass weeds such as tall fescue, Bermuda grass, nimblewell and quack grass prior to the soil preparation process. Glyphosate, applied in accordance with label directions, will control most perennial grassy weeds. Begin treatment with glyphosate 30 to 45 days prior to renovation to provide the opportunity for retreatment if regrowth occurs.
Perennial broadleaf weeds can be controlled either prior to renovation or after the new seed has been mowed two times. If you are attempting to control broadleaf weeds prior to renovation, apply the broadleaf weed control at least 30 days prior to verticutting and seeding.
Dethatch if necessary. Use a vertical mower or dethatching machine to cut grooves in the soil so that seed can make good soil contact. Seed planted on top of the thatch layer is largely wasted, as thatch is a hydrophobic layer of decomposed organic matter. Because of its high cellulose content, it is slow to decay and forms a semiwaterproof mat between the soil and grass leaves.
If there are low spots in the lawn, they can be filled and leveled with good topsoil. Apply the lime and fertilizer based on the soil test recommendation.
Seed may now be sown. The ideal seeding period for lawns is mid-August through the end of September. Renovated lawns can be drill-seeded as well as broadcast-seeded. Drill-seeding provides the best seed to soil contact and the highest germination rate. Drill-seeding alone generally leaves a "row effect," which can be masked also by broadcast seeding. The best method involves drill-seeding in two perpendicular directions and then broadcast-seeding. Lightly rake or drag the area after seeding.
An important key to quick and successful establishment is to water frequently. Water lightly and frequently every day until the seed has germinated, and then water less frequently but more deeply, to keep the soil moist.
Begin mowing the new lawn when the height the of grass is one-third more than the intended mowing height. Be sure the lawn mower is sharp. A dull mower tends to pull grass seedlings out of the ground. Also try to minimize traffic on the new lawn until it is mature.
During the next several months you could begin a good comprehensive fall fertilization program based on the recommendations from Virginia Cooperative Extension. A future article will cover this topic.
Joe Hunnings is the Virginia Cooperative Extension agent for agriculture in the Montgomery County Extension Office in Christiansburg. If you have questions, call him at 382-5790.
by CNB