Answer: Whether you start your lawn by planting grass seed or by installing sod, you still need to pay attention to proper soil preparation first. Without good soil, neither one will stay healthy in the long run.
You will need to loosen the soil down about six inches, add organic matter such as compost, and then add fertilizer and possibly also lime as indicated by soil tests. (Soil tests are really important, testing is the only way to know which fertilizer to use and whether or not you need to add lime.)
Then you would seed or sod. Sod gives the "instant" lawn but is more expensive than seeding. Both require follow up care such as watering and frequent mowing while they become established.
I should also mention that late summer to early fall is really the best time of year for major lawn work.
Your Cornell county extension should be able to help you with the soil testing and recommend the best varieties of grass for your yard, they should also be able to advise you on seeding, sodding, and lawn maintenance. In the meantime, here is their web site with a lot of lawn information you may find helpful.
Good luck with your lawn this year!
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