Step 4: Improve the soil
Don’t think you can fix bad soil just by adding a few inches of black soil on top of the old. Instead, spread the conditioners, recommended by the soil analysis, across the entire lawn. Then rent a tiller and till them into the soil to a depth of about 5 in.
‘Adding good-quality black topsoil over bad soil is like putting chocolate frosting on a stale cake?it doesn’t fix the underlying problem.’
Bob Mugaas, Turf Expert