How to Plant Grass Seed for a New Lawn

Planting grass seed is more economical than laying down sod, but the process will require some time and patience before you see results. The type of seed you use will depend on your climate, so read the label on your grass seed carefully. 

For cool-season grasses common in Canada such as fescue, ryegrass and bluegrass, growing grass from seed in spring or early fall is ideal because the temperatures promote grass seed’s natural growth cycle. If planting grass seed in the spring, ideal soil temperatures should be around 15 degrees Celsius for seeds to germinate. The level of moisture in the soil and cooler air in spring and early fall really help cool-season grasses take root and grow successfully.

If you’re looking to plant a new lawn but don’t want to wait several weeks to see results refer to our guide:

Measure the size of your yard, then buy the seed you need—the exact amount will depend on the variety of grass, as well as the size of your yard.

How much grass seed will you need to plant a new lawn? Most grass seed packaging will specify the maximum square feet one bag of grass seed will cover. For example, a 1 kg bag of seed covers an average area of 2,500 square feet.

A few days before planting, water the lawn to a depth of 6 to 8 inches. Plant when the surface of the soil is dry.

If you’re starting with soil, you’ll need to take a few steps to prepare. Rake out any debris and stones, then grade the yard so it’s level. You should also enrich the soil before planting.

Check to make sure you’re not dealing with compacted soil. Some tell-tale signs of soil compaction are pooling of water or the ground feeling hard underfoot. You may need to work compost or fresh seeding soil into the existing dirt with a rake or tiller to loosen it. Either way, enriching the ground with fresh soil will help grass seed germinate.

Smooth the area with the back of a rake to give the soil its final grading before planting grass seed. Your goal is to break your soil down to pea- or marble-sized particles, which serve as welcome mats for grass seeds.

If you’re looking to repair your existing lawn rather than grow one from scratch, refer to our guides:

Seed is applied at a rate of so many pounds per 1,000 square feet, depending on the seed. Because drop spreaders are calibrated for fertilizer rather than seed, you'll have to lay out an area of 1,000 square feet on your own. If the area is irregular or involves several parts of the lawn, mark the boundaries with flour, chalk, or landscaper’s paint.

Weigh the amount of seed in the package. Divide the total weight into the amount you need to spread per 1,000 square feet. Put one-half the amount of seed needed per 1,000 square feet in a drop spreader. For smaller areas, you can use a hand spreader.

Using a lawn spreader is highly recommended to get even coverage of seed. Some grass seed brands come with spreader settings right on the packaging. If there are no settings on the bag, place half the amount of seed to cover the area. Set the lawn spreader on a low setting and walk back and forth in rows across the lawn. Shut off the hopper at the end of each row and begin seeding again once you've made the turn. Continue until the spreader is empty.

Make a second pass. Put half the amount needed per 1,000 square feet in the empty spreader. Make a second pass across the soil, perpendicular to the first.

Don’t apply weed killers once you plant grass seed. Wait until the grass has grown at least an inch and been mowed a few times since weed killers can prevent the grass seed from sprouting.

The seeds need good contact with the soil in order to germinate. Rake the soil lightly to cover the seeds with no more than 1/8 to 1/4 inch of soil. It's hard to not cover some of the seed with too much soil. The amount is about right when only about 10 percent of the seeds are visible. It's an art, rather than a science, so trust your eyes.

A light rolling does the job without compressing the soil too much. Roll the lawn with a roller meant to be filled with water but don't put any water in it.

Starter fertilizers have a high phosphorus content which promotes the strong root system needed for a thick and healthy established lawn. When first learning how to plant grass seed, follow the instructions on the bag for proper application rates. A lawn spreader is always recommended for application of fertilizer products to provide an even coverage and prevent applying too much in one location, which can burn the new lawn.

Mulching the seed helps keep moisture in the soil and helps prevent erosion until the grass is established. Wheat straw is the traditional lawn mulch, but it sometimes contains weed seeds. Check with your local garden centre for a suitable straw or other mulches.

Water the turf two to four times a day. If the seeds or seedlings dry up, they will die. Water frequently at the beginning, applying enough water to moisten the soil to one to two inches deep. As the grass starts to sprout and take root, gradually reduce the watering frequency until you reach a normal frequency. It can take some grass seed varieties up to 3 weeks to germinate, so water until your lawn is well established.

Mowing encourages grass plants to spread out and fill in the lawn. Begin mowing when the plants have reached their typical mowing height, and never take off more than one-third of the leaf blade at a time. For example, cut cool-season grasses back to 2 inches once they reach a height of 3 inches. Adjust your mower to high setting to keep the lawn nice and thick. When you cut it too short, weeds can sneak in.

Once the grass is four to six weeks old, fertilize it, using a high nitrogen slow-release fertilizer. Feed every eight weeks after until fall when a fall lawn food application will help the new lawn survive the harsh winter weather.