Kentucky Bluegrass prefers rich fertile soil, well-drained with lots of sun. The underground roots spread to fill in thin areas to make a thick lawn. Kentucky Bluegrass goes dormant in hot, dry weather but it will recover when rain and cooler temperatures return. It can take up to 28 days for Kentucky Bluegrass to germinate under ideal conditions. Lateral spread. 1 bag can seed up to 474 sq.ft.