Homeowners can perform grass seed application by hand, but better results are likely with the use of a manual broadcast seeder. It is sometimes possible to rent a commercial turfgrass planter for planting grass seed, which will sow the grass seed in wide rows.
When starting a new lawn, the soil should be fully prepared before grass seed application is begun. At the least, the ground should be cleared of weeds and debris and leveled. The soil should be tilled and then dragged or raked smooth. More complete soil preparation involves digging the area to a depth of six or eight inches, mixing in soil amendments, raking, and allowing the soil to settle before putting out the seed.
The amount of seed needed for grass seed application over a specific area will be determined by the type of seed or seed mix used, the acidity or alkalinity of the soil, and the growing conditions. In the United States, the local County Extension Service can provide advice about the best choices for applying grass seed in that particular location. Grass is particularly responsive to the amount of available light, so be sure to choose the right kind of grass seed for a sunny or shady location.
Whether seed is broadcast by hand or by a seeder, grass seed application should always be done in two directions to provide the best possible coverage. For example, the lawn could be seeded moving east to west. It should then be seeded again moving north to south. Use half the total amount of seed for each direction of application.
Once the lawn is seeded, the area should be lightly raked or dragged. Grass seed germinates best with about 1/4 inch (0.6 cm) of soil cover. The area should be kept evenly moist throughout the germination period for best results.
Old lawns are often rejuvenated by overseeding. The lawn should be raked carefully before beginning grass seed application, to remove all the dead grass and thatch. Broadcast in two directions during the application, but use about half the amount of seed required for a new lawn. Keep the lawn moist for good germination.