A lawn can develop bare patches or become weedy over time, so the lawn benefits from reseeding to give it that new lawn look. In warm areas of the United States, reseeding provides a green lawn over winter when warm-season grasses become dormant and turn brown. Select the best grass variety for your lawn, and prepare the area before reseeding for the best results. Late summer is the best season for reseeding with cool-season grasses. Reseed a warm-season lawn in fall for winter color, or in spring or early summer to improve patchy grass.
Selecting Grass Seed
The best grass variety for reseeding depends on the growing conditions and the reason for reseeding. Some common lawn grass varieties are:
- Tall fescue (Festuca arundinacea), which is a cool-season grass that's hardy in U.S. Department of Agriculture plant hardiness zones 4 through 7 and grows well in sunny and partially shaded lawns.
- Perennial ryegrass (Lolium perenne),
a grass for high-traffic lawns that grows in USDA zones 7 through 9.
- Bermuda grass (Cynodon spp.), which is a warm-season grass that's hardy in USDA
zones 7 through 10 and grows well in sunny
spots and at high temperatures. This grass has a tendency to become invasive.
- Annual ryegrass (Lolium multiflorum), a grass variety that provides winter color in a warm-season lawn.
Select the same grass variety as the current lawn grass or one that's a similar color and texture for an even, finished effect.
Grass doesn't compete well with weeds. For reseeding to be successful, weed infestations must be controlled. Remove small weeds by digging them up with a narrow trowel, or if the lawn is heavily infested, apply a herbicide five to seven days before reseeding.
Before applying the herbicide, allow the lawn to grow 1 to 2 inches taller than normal so the weeds absorb the chemicals over a large surface area.
Put on long pants, a long-sleeved shirt, gloves and safety goggles, and apply a lawn herbicide on a dry, still day. A ready-to-use product containing 0.1 percent quinclorac, 0.22 percent mecoprop-p, 0.12 percent 2,4-D and 0.05 percent dicamba can be applied when temperatures are below 90 degrees and above 45 degrees Fahrenheit. Spray the herbicide on the center of each weed. This weedkiller controls broadleaved weeds and some weedy grasses.
Check the label before applying a lawn herbicide. Some are harmful to certain grass varieties.
Preparing the Lawn
Mowing a lawn removes excess grass, readying it for reseeding, and dethatching and aerating help prepare the soil. Mature lawns are often covered in thatch and drain poorly, and grass seed struggles to grow. Thatch is the layer of moss, dried grass clippings and other plant debris. Mow your lawn with your lawn mower set on its lowest setting.
If the thatch layer is thicker than 1/3 inch, remove the thatch with a dethatcher, which rakes out thatch with vertical blades. Run a lawn aerator over the lawn. This remove plugs of soil, helping to break up compacted soil.
Fertilizing the Lawn
Grass seed benefits from fertilizer to help it grow and become established. Evenly apply a lawn starter fertilizer, such as a 20 pounds of 5-10-5 fertilizer or 10 pounds of 10-20-10 fertilizer per 1,000 square feet, and rake it into the soil surface and then water.
Sowing Grass Seed
Spreading grass seed evenly and at the correct rate helps avoid uneven or bare patches when reseeding a lawn.
Scatter grass seed or use a broadcast or drop spreader. Divide the seed into two portions, and spread one portion side to side across the lawn and the other portion up and down the lawn. Sow the seed two to three times more thickly on bare patches.
Sowing rates for grass seed are usually given per 1,000 square feet, according to the grass variety. Tall fescue is sown at a rate of 8 to 10 pounds per 1,000 square feet, and perennial rygrass is sown at a rate of 6 to 9 pounds per 1,000 square feet. The sowing rate for Bermuda grass is 1 pound per 1,000 square feet, and the rate for annual ryegrass is 7 to 9 pounds.
Rake the grass seed into the surface 1/4 inch of soil.
Irrigating After Sowing
Irrigating the lawn regularly for four to six weeks after sowing provides the evenly moist soil grass seed needs to sprout and grow well. Keep traffic to a minimum during the germination time.
Water the lawn immediately after sowing and whenever the soil surface is dry, applying enough water to moisten the soil to a depth of 4 to 6 inches, but don't water so much that the soil becomes soggy.