Aeration is also called core aeration. This is an important service for all lawn varieties. Aeration is the process of perforating the soil, by removing a core or plug of soil and depositing that core on the surface to break down. The aeration process also helps to remove any thatch layer that might exist, although some lawns may still require dethatching.
Warm-season grasses such as Bermuda, Zoysia, St. Augustine, and Centipede should be aerated after they have fully returned from dormancy and are in their peak growing season. The timing of this depends on location but typically occurs between late May-July. Warm-season turf does not require overseeding.