Most grass types grown in Tennessee can be planted anytime in March. Sow tall fescue, Kentucky bluegrass and timothy grass as early as February 1, and as late as April 1. Orchardgrass cannot be planted in March because it needs a fall planting.
Wait until the danger of frost has passed to plant grass seed. This is especially important if Tennessee is experiencing a late thaw.
Amend the soil in the September before planting time. Get a soil test done and amend the soil with lime (must be done six months in advance). For even better grass growth, spread 40 lb. of nitrogen per acre at planting time.