Good looking lawns require periodic makeovers. No matter how well it is cared for, grass shows its age after several years. Tired grass plants thin out, allowing weeds to invade the bare spots. Unless you take steps to restore the health and vigor of the lawn, it will decline.
Routine Maintenance - The easiest way to insure a beautiful lawn for the long term is to overseed the existing turf every four or five years or when it is about 25% weeds.
Renovation – Renovation means building brand new turf, virtually installing a lawn from scratch. At this time the soil can also be improved. Consider renovating lawn areas that are about 50% weeds.
If you have an existing lawn of perennial ryegrass, tall fescue, Kentucky bluegrass or a combination of these cool weather grasses you must decide whether you want to renovate with grass seed or with sod. (Warm weather grasses grown in the South are typically grown with sprigs or plugs).
It takes a bit more energy, but renovating with sod produces an instant finished lawn. Unlike seeded lawns that require overseeding the second year to achieve satisfactory density, sod creates a full, lush lawn immediately. Grass plants in sod are professionally raised under optimum conditions and are so densely planted there is no space for new weeds. With sod you also have an opportunity to upgrade the soil that the new grass will be growing in. This assures a healthier, more self-reliant lawn for a longer time.
Choosing Turfgrass Sod
Choose healthy turfgrass sod to successfully renovate your lawn. It should be fresh, harvested within a day or so of use. Look for rolled or folded strips of sod with grass at least 2 inches long and a uniform green color. The soil on the underside of the sod where the grass roots are should be dark and moist. It should be no thicker than 1 inch, showing a tight matrix of healthy roots.
Sod is available in many types of grass, and combinations of several grasses. If your existing lawn is mostly bluegrass, choose a sod that is all bluegrass. Most lawns are a mixture of several grasses--perhaps Kentucky bluegrass plus turftype fescue and some perennial rye as well. There is sod made of mixed grasses for this type of situation.
When to Renovate with Sod
Sod composed of one or more northern (cool weather) grasses can be installed successfully in spring or fall. In fact, it can be laid almost anytime of the year that the soil is not frozen. Because the roots of the grass plants are already developed to some degree, it does not require as long to become established.
Do not buy sod until you have fully prepared the soil on which it will be installed. Order it from the nursery to be delivered within 8 hours of harvest, if possible. Plan so you or your landscape contractor are prepared to lay it promptly. Store it in the shade and keep it moist if there is any delay.