Over Seeding Residential Lawns
What is the fall cutoff date for over seeding lawns in SE Michigan?
Wayne County Michigan
There is no actual cutoff date, just periods when overseeding will be more successful. Some will even do a dormant seeding, after the lawn has gone dormant for the winter. Results are always iffy for dormant seedings however, as to how much germination will actually occur, sometimes a fair amount, sometimes none at all depending on winter weather conditions. The ideal time to seed reseed is end of August, early September for creating good establishment, when several mowings can be accomplished before dormancy. Success is less predictable as it gets later in the year. Read more here: https://www.canr.msu.edu/news/late_season_lawn_seeding
and here: https://www.canr.msu.edu/news/is_it_too_late_to_seed_turfgrass_this_fall: