Lawn care calendar for North Carolina: when to fertilize and seed

Windows follow NC State's regional tables in the source; a mountain lawn runs earlier in fall and later in spring than a coastal one.

Which grasses grow where in North Carolina

NC State divides the state into mountains, piedmont and coastal plain. Tall fescue, Kentucky bluegrass, fine fescue and perennial ryegrass are the cool-season lawn grasses, mostly used in the mountains and piedmont. Bermudagrass, zoysiagrass, centipedegrass, St. Augustinegrass and carpetgrass are the warm-season group, mostly recommended for the piedmont and coastal plain. Perennial ryegrass is adapted to the mountains and is always blended with another grass, never seeded alone.

Mowing heights from the same guide: tall fescue 3 to 3.5 inches and never under 2.5; Kentucky bluegrass 1.5 to 2.5 inches alone or 2.5 to 3.5 inches with tall fescue; bermudagrass 0.75 to 1 inch with a reel mower, or 1 to 2 inches with a rotary; centipedegrass when it reaches 1 inch and no higher than 2; St. Augustinegrass 2.5 to 4 inches during the growing season.

Frost dates from NOAA

Dates are the NOAA 1991-2020 normals for the last spring and first fall 32 F freeze at 50% probability. Asheville Regional Airport averages April 9 and October 28. Charlotte Douglas is March 30 and November 3, Raleigh-Durham International is March 31 and November 4, and Wilmington International is March 19 and November 20.

Our arithmetic from those dates: Asheville has about 202 days between its average last and first freeze, Wilmington about 246. That 44 day gap is why the mountains and the coast cannot share a calendar.

Spring

Warm-season lawns are slow to green up. Seed them from March 1, though NC State lists different end dates by species, and lay sod only once soil has stayed above 55 F for several weeks, because sod will not root in colder soil. A new seeded lawn gets its first feeding six to eight weeks after the seedlings emerge, at about 1 pound of nitrogen per 1,000 square feet. Count a new lawn as established after three mowings.

On cool-season lawns, spring is one of the two main feeding windows. Core aeration works in early spring on compacted soil, as long as the grass is actively growing. Where crabgrass is a problem and you are seeding in spring, NC State names siduron as the pre-emergent that does not block cool-season seed.

Summer

Warm-season grasses do their growing now, and bermudagrass wants frequent low mowing. Tall fescue and bluegrass slow down. If you feed cool-season turf in summer to help color or recovery, NC State caps it at 0.2 to 0.5 pound of nitrogen per 1,000 square feet, and warns that late spring and summer nitrogen on tall fescue can call for a fungicide.

Water established lawns to a depth of 6 to 8 inches. About 1 inch a week works, applied as roughly half an inch every three or four days, and 1 inch on 1,000 square feet takes 640 gallons. Kentucky bluegrass usually recovers from a two to four week drought without help. A dormant lawn needs about a quarter inch every three weeks to keep the growing points alive.

Fall

Fall is the main season for cool-season lawns: seed between mid-August and October 1, use 6 pounds of seed per 1,000 square feet for tall fescue and 1 to 2 pounds for Kentucky bluegrass, and core aerate or renovate while the grass is growing. Seeding after October 1 is where winter injury begins to cost stands.

Warm-season lawns stop at the first heavy frost. Keep nitrogen off them from late fall through winter, and plan thatch work for their own season: NC State says to power rake and core once thatch passes three quarters of an inch, and to core warm-season grass in late spring or early summer.

Soil tests, lime and the bag math

Test the soil at least every two to three years. Most North Carolina soils are acidic, and the target pH is 6.5 to 7.0 for most turf, or about 5.5 for centipedegrass.

To turn a target into a bag weight, divide 100 by the first number on the label: a 16-4-8 bag takes 6.25 pounds to deliver 1 pound of nitrogen per 1,000 square feet. The lawn fertilizer calculator on this site does that division for any bag and lawn size.