How to Slit Seed a Lawn

Prepare your lawn for seeding in early fall or spring so that the grass you are seeding has time to become established before winter cold or summer heat.

Mow the lawn to the lowest safe level for your grass variety. With most grass types, this is typically 1 to 1 1/2 inches. This will allow sunlight to reach the grass seed and help it to germinate.

Obtain a slit seeder from a garden center. You can typically rent machines such as this for one-time use. A slit seeder gouges out shallow furrows in your grass and topsoil to allow grass seed the chance to reach the soil so that it can sprout and then places the seed directly into the furrows.

Divide your grass seed in half. Place half of it in the slit seeder.

Place your slit seeder at one end of your lawn and slowly push it over the lawn in a grid pattern until you have completely seeded your lawn. A vertical mower operates similarly to a lawn mower in that it has a pull-rope start and similar choke, throttle and speed levers. Make a second pass with your second half of the seed. Vary the grid pattern by 90 degrees.

Water your lawn to germinate the seed and promote its growth. Keep your grass mowed to the shorter length until the newly seeded grass reaches this height. Then lift the decking of your lawn mower and allow the grass to grow back to its tallest healthy length. Most grasses thrive best when they’re mowed at 2 to 2 1/2 inches.