im adding a core aerator and dethatcher for first time . and im aiming to improve customer lawns without a license to apply chemicals . thusly im wondering what a non licensed person can apply ? and besides aerating / dethatching / top feeding / seeding what other methods folks use to revitalize lawns ? as of now im lookingat soil tests and liming if called for as a basic first step strategy , liming because weve alot of acidic soil conditions on our route caused by mature broad leaf trees such as white oaks and ive never seen lime do anything but good on local lawns .