Depending on your location, your lawn might feature cool-season grasses, warm-season grasses, or a combination of both. Each type has different growth periods, which affects the best time to plant your seeds. “The goal is to establish deep root systems to survive the hot and dry summer season for cool season grasses and the hard, dry freezing weather for warm season grass,” says Craig McManus, host of The Garden Question Podcast and founder of McPlants, a boutique garden design-build company. Timing is key to ensuring your lawn thrives.
First, you need to determine which type of grass is suitable for your climate. Cool-season grasses such as fescue, Kentucky bluegrass, and perennial ryegrass are most active during winter and early spring, flowering and setting seeds by early summer, then going dormant in the southern heat.
Warm-season grasses, including zoysia, St. Augustine, centipedegrass, Bermudagrass, and buffalograss, on the other hand, thrive in the heat and have their growth spurt in spring. These grasses bloom and set seeds during summer and early fall, before winter returns. They are more common in southern regions, while cool-season grasses are prevalent in the north. In the central transition zone, both types can coexist, with cool-season grasses in shady spots and warm-season grasses in sunny areas.
The type of grass is the primary factor in determining seeding time, but local climate conditions also play a role. Spring and fall can vary significantly across different regions, affecting the timing for planting.
For warm-season grasses like Bermudagrass, zoysia, or centipedegrass, the best time to reseed is late spring to early summer. “With warm season grass it is best to sow seeds when nighttime temperatures reach 70 degrees consistently,” McManus suggests. Warmer soil temperatures help with germination, and the absence of frost protects the seedlings. Planting in late spring or early summer allows these grasses ample time to establish before winter sets in.
For cool-season turfgrasses like turf-type fescue and Kentucky bluegrass, early autumn is ideal for seeding. “You will see the best results when seeding turf type fescue and Kentucky bluegrass at the beginning of the cool season, approximately ten weeks before the average first frost date,” McManus advises. This gives the seedlings time to develop deep roots, helping them endure the hot, dry months of July, August, and September.
Spring is the second-best time for seeding cool-season grasses, but it doesn’t allow as much time for the grass to mature before the summer heat arrives. If spring is your only option, you might want to consider laying sod instead of seeding, particularly in southern areas, as mature sod is more resilient to stress than young seedlings. Timing might vary slightly if you’re starting from sod or plugs.
