The answer to 'frequency of aeration' is that most lawns should be aerated once a year, typically in the fall. Aeration is the process of perforating the soil with small holes to allow air, water, and nutrients to penetrate the grass roots more effectively. This helps to reduce soil compaction and improve the overall health and appearance of your lawn.
The ideal time to aerate your lawn is when the grass is actively growing, which is usually in the fall for cool-season grasses and in the spring for warm-season grasses. Aerating during these times allows the lawn to quickly recover and fill in the holes left by the aeration process. It's important to avoid aerating during periods of drought or extreme heat, as this can stress the grass and lead to damage.