A little work and effort in the fall will pay big dividends in the spring and all of next summer with a great looking and disease free lawn.
Mowing: Cool season grasses like fine lawn fescue, Kentucky bluegrass and perennial ryegrass grow fastest in the spring and fall and should be mowed with a sharp blade right up to the first frost.
Aerate: Aeration loosens up compacted soil and allows your lawn to easily absorb nutrients, air and water into the soil. The plug aerator is most efficient and those unsightly plugs will dissolve into the soil. Schedule your aeration two weeks before your last application of fertilizer. An aerator can be rented for the day from your local tool rental merchant.
Fertilizing: September and October are the best months for fertilization and is best scheduled after aeration. Start with a soil test from your County Extension Service. While initially created to assist farmers, in our urban centers they now have Horticulture Specialists that offer assistance to all of us city dwellers. For a modest cost they will test your soil sample and make recommendations of the proper amounts of fertilizer and lime that will provide the nutrition your lawn needs and save you money by not over fertilizing.
Grub and Weed Control: Adult beetles lay their eggs in the yard in July and August. If not controlled, their maturing larva (grubs) will damage your yard all winter and that damage will not be visible until spring. Apply your pesticides during this active season. Follow the label of any product you use and be careful around children and pets. This is a great time to get your broadleaf weeds under control as well. Time your application for dandelions and ground ivy for after the first frost in the area.
Overseed: Fall is a good time to overseed your bare and damaged spots while planting trees and shrubs. Rough up the soil to make sure you have good seed to soil contact and water your newly seeded areas and plants well. Time your seeding around your herbicide applications.
Click on the video below for information from Penn State University and check with your local extension service to help you set up a year round management plan for your yard.