New lawns can be started by laying sod squares, or by growing new grass plants from seed. Growing a new lawn from seed is cheaper than sod, although the lawn takes longer to become established. If you plant grass seed, take measures to keep wind and water from relocating the seed after planting. Even a modest flow of water from a sprinkler can relocate grass seed from a slope to the bottom of a hill. You can use a roller on the soil before and after seeding.
Dispersing grass seed
Plant grass seed in topsoil that has been loosened to a depth of 7.5 to 15 cm (3 to 6 inches). Loose soil will make it easier for new seedlings to set down roots and allow the lawn to become established more easily. Loose soil also allows grass seeds and seedlings to be anchored and more resistant to wind and water dislocation. Plant seed at the density per unit area specified by the supplier. Avoid sowing seed on windy days, as it will travel great distances in even a slight wind.
Rolling the seed
After the seed has been scattered evenly, a large roller is used to set the seed into the soil. By pressing the seed into the surface of the soil, the roller prevents the seed from being blown by wind or washed away by water. Do not over compress the seed. Grass seed should be visible on the surface after rolling. A single pass with a roller is recommended, and if you can control the weight of your roller, use the minimum weight to press the seed into the surface of the soil.
Rolling before seeding
You can also roll the soil prior to scattering seed. This step can help set the contours of your new lawn and prevent low spots from forming later. Make a single pass with a roller, and do not over compress the soil. After rolling, you should still be able to create slight footprints when walking on the soil. After rolling the topsoil, lightly rake it to loosen the surface before scattering seed.