A slit seeder is a reseeding or overseeding tool that passes over your lawn, depositing seeds in small slits, giving them better contact with the soil and higher germination rates. Slit seeders are often used on grass lawns that have suffered severe damage from drought, pests or disease. Your lawn will require some preparation before it is slit-seeded. This will help to retain as much of your existing grass as possible and will ensure that the slit seeder does not encounter potentially damaging obstacles.
Remove all branches, rocks and other debris from your lawn.
Dig up the root systems of all weeds in your lawn by hand to prevent them from growing back. If that is impossible, cut weeds back to the ground with a lawn mower. Then, when they grow back two to three inches, spray them with a non-selective herbicide (make sure the type of weeds that you are spraying are listed as target weeds on the back of the bottle). Herbicides are only optimally effective when sprayed on actively growing weeds. Be sure that the weeds are gone for good before planting new grass seed. Newly seeded lawns should not be walked on or treated with herbicide.
Cut your remaining grass as low as possible.
Give your lawn 1 to 2 inches of water the night before you slit seed. Hydrated roots stand a greater chance of recovery than thirsty ones, and moist soil is easier for the slit seeder to slice through.