Answer: You didn't indicate what grasses are in your lawn and there are different practices, depending upon grass types. However, if you visit the following website hosted by NC State University, you'll find a link to a lawn care calendar for each of the most popular grasses grown in your area. I think you'll find answers to all your questions here. http://www.turffiles.ncsu.edu/pubs/management/ag367.html
Best wishes with your landscape!
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