Mid to late August is the optimal time to seed cool-season turfgrasses throughout much of the northern half of the United States because soil and air temperatures tend to be moderate, falling into the zone where maximum germination can occur. The optimum air temperature is 60-85°F, depending on the species. Spring seeding is usually recommended as the second best time to seed. However, to avoid the potential problems of seeding too late in the spring, dormant seeding has distinct advantages.

So, what is “dormant seeding?” Dormant seeding is the distribution of seeds during a period outside the normal growing season, so that the seeds will be in place and ready to germinate when conditions allow. Ideally, the weather is persistently cold, to prevent premature germination. Snow cover is also beneficial, because it keeps the seed moist. In Ohio, dormant seeding is done by seeding into a prepared soil after soil temperatures have cooled below 40°F so the seed will not germinate until spring 2004.

Research on dormant seeding practices has revealed the following: