Answer: Generally speaking, the best time of year to do extensive lawn work is early fall. Your local county extension should be able to help you run the necessary soil tests and recommend specific soil preparation such as fertilizer and lime, the best grass variety to use, and help you set up a lawn maintenance program based on the growing conditions in your yard.
In the meantime, you may find the following information helpful. (You may need to cut and paste the complete url to make it work correctly.)
Good luck with your new lawn!
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