Cool-season grasses common in northern lawns should be aerated in the early ... through grass and thatch into the soil. Core or plug aerators often are preferential for lawn professionals.

Plug, or core, aerators are the way to go if your soil ... It is best to avoid aerating lawns when they are going into dormancy. So, late summer or early fall are too late for warm-season grasses ...

Spike aerators don't remove the plug. While they do allow water and nutrients ... They're great for larger lawns that would take forever to do by hand. Look for one with at least two height ...