This one gets me in trouble with equipment rental companies and lawn services that do a lot of aeration and dethatching. It also runs counter to the way grandad took care of his lawn. But I will say it anyway….
Very few average lawns with proper watering practices and mowing practices require either service. At all. Ever.
Compaction of soil serious enough to need mechanical aeration is almost always a result of overwatering. High traffic areas can be compacted, but typically, it goes hand in hand with overwatering, and soil that remains wet too long. Mechanical aeration typically does more harm than good. It brings weed seeds to the soil surface, and creates an uneven lawn over time, as the soil plugs break down and after several years begin to form bumps and ridges. It also disturbs the flora and fauna of the soil. It’s just not a great practice in the 719, and my experience is that it provides few tangible results. If dry soils are struggling to absorb water, wetting agents (like Revive) and humic acids are better solutions to improving water absorption, with the added bonus of helping to build soil structure as well. There are certainly situations that require aeration, but as a rule, it is not something that most lawns need every year, or require to be healthy. It should be more of a drastic remediation tool than an annual maintenance tool.
Dethatching is necessary only if poor mowing practices have left such a deep layer of dead grass and clippings on the soil that it begins to smother the grass underneath. Otherwise, even the woody stems will break down or be consumed by soil critters in a year or less. If drought or other stress has killed all the grass, dethatching the surface may help as a part of prep for new seed. Dethatching is a mechanical process that, like aeration, disturbs the top layer of soil and can bring weed seeds to the surface to germinate. It’s not a service that brings any tangible ROI in my opinion, at least not for most homeowners. If properly cut and cared for, your lawn that was dethatched will not be any better than your neighbor’s that wasn’t, by midsummer all other factors being equal.
Cut your lawn once a week, rake up any thick extra clippings the mulch mower leaves behind after especially wet weeks, and your lawn will not require dethatching.
While I am at it, I definitely suggest using the organic based dehydrated poultry waste fertilizers like Rick’s branded one, or Richlawn (available most everywhere). They contribute to better soil structure, are gentle on the soil, and do not contribute to forming mineral hardpan under lawns.