In central Ohio, the entire month of September is acceptable for seeding. Lawns seeded later in the fall may fail because the seedling turf has insufficient growth to survive the winter.
If seeding cannot be done by before October 20 in central Ohio, postpone the job until spring. The earlier in the spring a seeding can be made (preferably March) the better the chances for success.
Unfortunately, all lawns cannot be seeded during the recommended late summer/early fall period. Besides the summer survival risks associated with spring seedings, these spring seedings also will be susceptible to heavy infestations of summer annual weeds including crabgrass, foxtail, barnyardgrass, pigweed and many others. Infestations of these summer annual weeds are greatly reduced in successful early fall seedings, since a good density develops before the weed seeds germinate the following spring.
Look for grass blend contain a variety of grasses or blends and be aware of the amount of sun or shade your seeding area receives daily. Sow seed, most recommendations call for 2-3 lbs per 1000 sq foot, evenly with a spreader. Plan to go over the area to be seeded twice, preferably in a different direction each time. With a low seeding rate, it is easier to get good distribution if something is added to the seed to make more bulk. Several materials such as sand or corn meal may be used. Starter fertilizer should be applied just prior to or after seeding.
The soil should be raked lightly to cover the seed with 0.1 to 0.3 inches of soil. If some seed can still be seen after raking, they have not been covered too deeply. Apply a mulch after seeding to ensure optimum moisture conditions and reduce erosion. Straw applied in a thin layer is a very satisfactory mulch. Straw spread uniformly at 50 to 80 pounds (1-2 bales) over 1,000 square feet of seeded area is about the proper rate. When the job is finished there should be half soil and half straw when looking directly down on it.
The lawn should be irrigated and the surface kept moist. This usually means sprinkling the new seeding lightly at least twice a day, sometimes more often, depending on how hot the weather is and how often it rains. After the seedlings emerge and begin to establish, the interval between waterings can be lengthened provided adequate moisture is available for seedling growth.