Core aeration has several benefits. Breaking up compacted soil helps your turf acquire water and nutrients more efficiently. Basically getting the fertilizer and water to the roots. Increases water absorption. Helps with run off, therefore using less water. Aids in dissipating thatch buildup. Encourages new root growth. Usually once a year in the fall is adequate. In the spring before your first application of pre-emergent is also beneficial.
Overseeding after core aeration in the fall is recommended to establish a thicker lawn. Or to repair damaged turf. Broadcasting grass seed followed by a starter fertilizer will give your lawn a head start come next spring. Best time to core aerate is after a decent rain. You want the soil to be moist and workable but not saturated. Select a seed which is best suited for your area. Then a starter fertilizer such as 18-20-3.
Caution: if you have an irrigation system make sure you flag the sprinkler heads before aerating.
You can either hire a contractor to do the work or do it your self. If you have a small yard, lets say under 20k, I would recommended hiring a contractor. Basically you would break even considering, rental, your time, and effort. Walk behind machines can be heavy and cumbersome to transport for the average homeowner. Operation of an aerator is straight forward yet once again it’s a cumbersome machine to run. If you have a large yard and the means to tow an aerator your job will be much easier providing your lawn is not to complex.
Cost to hire a contractor. Pricing will vary depending on your location. However roughly between $12 to $15 per 1000 sq ft with a minimum charge of $75 to $100 for aeration only. An additional charge $11 to $14 per 1000 sq ft for seed. Then approximately $5 to $7 per 1k for starter fertilizer. Seed and fertilizer will also have a set minimum in correlation with the aeration. All three would fall in the range of $28 to $36 per 1000 sq ft. Once again these prices are subjective. But it will give you some idea of cost. If your doing a complete lawn renovation you will incur additional cost for i.g application of Round-up or soil modification.
It’s also recommended to get a soil test. Poor soil conditions will lead to poor germination of seed. For example see lawn page for pH.
Most of us have a broadcast spreader. Be sure to properly calibrate your spreader according to the fertilizer your using. I advise using fertilizer and a spreader either made by the same manufacture or that endorse each other. Using off brand products my be cheaper, however you’ll pay later with the headaches of calibration. Usually overseeding requires anywhere between 3 to 7 pounds per 1k of lawn depending on thickness of turf. There is really no spreader calibration for spreading seed. Only advise I can give would be to know the size of your lawn and purchase the amount of seed you wold like to apply. A multi-pass method usually works well. Start by slowly applying the seed till your able to judge a setting which will give you the desire outcome.
It’s a good idea to try and time your overseeding so you can mow the new grass once or twice before a frost. This will allow the new grass to be more robust before the winter. Come next spring you will start to see the benefits of your work.