When starting a new lawn, many people wonder which is better: laying sod or sowing seeds. While laying sod is fast and produces high-quality new turf, seeding lawns are much cheaper and offer a wider variety of grass types. To learn which grass types are best for your area, contact a nearby extension service (many counties and universities have extensions), or ask an expert at a local garden center. Much of the labor of starting a lawn from seed is in the all-important prep work, but just as important is watering the seed and sprouts regularly until the new grass is well established.
Clear and Test the Soil
Remove any old grass plants and weeds from the area. You can dig out unwanted plants with a flat-bladed shovel, making sure you get the roots. Another method is to apply a non-selective herbicide (such as Roundup), then use a rented sod-cutter to remove the dead grass and roots. Take a sample of the soil and have it tested for soil pH. Most lawn grasses prefer a pH of 6.0 to 7.5. If the test reveals that your soil is overly acidic, you can "sweeten" it by applying garden lime.
Prepare the Soil
Break up the compacted soil with a rented tiller, or rototiller. Spread a starter fertilizer over the loosened soil. This type of fertilizer is high in phosphorus, the middle number in the NPK sequence on a fertilizer bag. Also, spread a soil conditioner over the soil. "Soil conditioner" is often what it is called at the store, but if you have a good supply of compost at home, it will serve just as well as a soil amendment.
Use the tiller to mix the starter fertilizer and soil conditioner (or equivalent) into the soil. Rake the soil to begin to level it out, removing any rocks and debris. To ensure proper drainage of surface water, make sure that any site grading you do allows water to flow away from your house. Finally, use a rented roller (with a water-filled drum) to finish leveling the soil. Water the soil lightly.
Apply the Seed
Follow the recommended seeding rate (as listed on the bag of grass seed) to apply the seed with a seed spreader. Spread 1/4 of the seed over the entire lawn area. Then, repeat three more times, each time using 1/4 of the seed. However, each of the four times you distribute a load of seed, push the spreader in a different direction, to encourage even dispersal. Rake the soil lightly to cover the seed with a thin layer of soil. Empty the water from the roller drum, and roll the lawn surface.
Water the Lawn
Moisten the soil carefully, using a fine spray from a hose sprayer. Be careful not want to over-water and create a flood. Repeat watering several times per day (depending on the weather) to keep the soil evenly moist. Do not let the soil dry out. The seeds will germinate and begin to sprout in about a week. Do not walk on or allow pets on any seeded area during this initial phase of growth. The soil is very unstable and any disturbance will produce lead to bare areas.
Mow and Care for the New Grass
Continue watering up to three times per day to keep the soil moist (it does not need to be wet) until the new grass is ready to mow: about 4 inches tall, or as recommended on the seed packaging. Mow the grass to no less than 3 inches in height (or as recommended). Make sure the grass gets plenty of water until it has grown enough to need three mowings. From that point on, water the grass with the normal schedule for the area, the current weather, and the type of grass. It's also a good idea to pull new weeds as they emerge to prevent them from spreading.