How to Plant Grass Seed

If you’re starting from scratch, follow the steps below to turn a patch of dirt into a verdant green lawn. Remember, if mowing and maintaining a lawn isn’t on the top of your priorities list, there are plenty of no-mow alternatives to a traditional grass lawn.

1. Prepare the Soil

Give your new lawn the best possible start by preparing the soil and planting site. Start by removing any existing weeds, then till the soil 8 to 10 inches deep. This often brings debris to the surface such as roots and rock, which should be removed from the planting area. Rake the area to create a smooth planting bed. You want the soil to be damp when seeding. Water the seedbed to a depth of 5 to 6 inches several days before you plan to seed. Just before planting, apply a “starter” fertilizer containing nitrogen, phosphorus, and potassium on the seedbed surface at a rate of 1 to 2 pounds nitrogen per 1,000 square feet.

2. Spread Grass Seed

Grass seed is spread across the soil surface using a drop spreader, which can be purchased at your local garden center or rented through an equipment rental service. The amount of seed needed is listed on the seed bag, typically as pounds of seed per 1,000 square feet (multiple the length and width of your planting area to determine how many square feet you have). You can adjust the spreader to distribute the appropriate amount of seed. To ensure even distribution, divide the recommended seed amount into two equal portions and spread each portion in a different direction across the seed bed. Mix the seed with sand, commercial soil, or a similar material before spreading to further aid in even distribution across the planting area.

3. Cover the Seeds

Grass seeds are small and do not need to be buried deep in the soil. After seeding, use a rake to lightly cover the seed with soil approximately 1/8-inch deep. Seeds need good contact with the soil surface to establish properly. Use a lightweight lawn roller to gently pack the seed into the soil, then cover the seedbed with a weed-free straw, such as wheat straw, or use an erosion control blanket. Covering the seedbed helps maintain soil moisture and prevents seeds from blowing or washing away. The mulch can be removed when a majority of the seed has germinated, and seedlings are one to two inches tall.

4. Water the Grass Seeds

Since grass seed is close to the soil surface, frequent, light irrigations are critical for keeping the seed and soil moist for proper germination. Water lightly each day for the first 10 to 14 days, making sure the upper inch of soil is moist. Switch to deeper, less frequent waterings once the seedlings are established to promote deeper rooting. Be careful not to let the soil dry out. You can begin mowing the new lawn when the turf foliage reaches the intended cutting height. Mowing will promote lateral spread.

How to Overseed a Lackluster Lawn

You can spread seed over an existing lawn to repair bare patches or thicken up thin areas. This process is called overseeding and is quite simple. Start by cutting the lawn very low and bagging the clippings. Rake the area you intend to seed to remove dead grass and debris, which will loosen and expose the soil for good seed contact. It is also a good idea to spread a very thin layer of topsoil, no more than ¼-inch thick, across the surface of the planting area and fertilize as described above. The remaining steps are the same as for establishing a new lawn: spread the seed according to label recommendations, cover with straw or a thin layer of topsoil, and water regularly.

When to Plant Grass Seeds

The proper time to sow grass seeds depends on your location and the type of grass you are establishing. Sow warm-season grasses from late spring to midsummer, after the threat of frost has passed and soils have warmed to 65 to 70 degrees Fahrenheit. This typically corresponds to daytime air temperatures around 80 degrees Fahrenheit. You can continue to seed warm-season grass into midsummer, allowing at least 90 days for the turf to establish before the expected first frost. Cool-season turfgrasses germinate best in early autumn, when air temperatures are more moderate and soil temperatures remain warm. As a rule of thumb, sow cool-season grass a minimum of 45 days before the expected first frost for your area. The second-best time to seed cool-season turfgrasses is in early spring, once soil temperatures have warmed to 50 to 60 degrees. Look for an inexpensive soil thermometer at your local garden center to help you take the guesswork out of when to plant.