Fescue grass is the most hardy and adaptive grass. It generally tolerates cold weather and foot traffic very well. However, it is still common for people to do a bit of overseeding in the early fall. Most of the time, overseeding is done in an attempt to thicken up the lawn or fill in some bare patches. The best time to overseed is in September, or after the growing season has begun to come to an end.
Use a thatching rake to remove thatch from your lawn. You may also choose to core the soil a couple weeks before reseeding to enhance seed-to-soil contact.
Mow the fescue grass shorter than you normally would, about 1 to 2 inches high, and remove any clippings left behind. If you have a mower that automatically bags clippings, this would be ideal.
Pour grass seed into a broadcast spreader. Set the spreading rate according to the manufacturer's directions. Push the broadcast spreader side to side over your fescue lawn and then up and down.
Rake over your entire lawn lightly. You can spread a bit of topsoil using the rake as well, but this is not necessary.
Water your lawn lightly twice per day until the grass seed has begun germination. This can take roughly three to four weeks. Once germination has taken place, return to your regular lawn maintenance.