Two different jobs, one material
North Carolina clay is the background condition for every lawn in the Triangle. It holds nutrients well and water poorly, it compacts under traffic, and in a graded subdivision lot the good topsoil is often simply gone. Top dressing is the long game against that β a thin layer of certified compost, repeated over seasons, that gradually improves structure and percolation.
The published benefits are substantial: reduced irrigation requirements and storm water runoff by up to 50%, improved percolation, better nutrient retention and uptake, reduced compaction, and lower pollutant loads in runoff.
Leveling is the other job. When a lawn has ruts, settling or low spots that hold water, straight compost will not hold a grade β so we use a 50/50 blend of compost and sand, which levels the way sand does while still feeding the soil the way compost does.
You cannot fertilize your way out of bad soil structure.
