Lawn care calendar for Florida: when to fertilize and seed

Dates shift with the weather; follow the signs in the text.

Which grasses grow where in Florida

St. Augustinegrass is the most widely planted lawn grass in Florida. It goes dormant in many parts of the state in winter, so skip fertilizer in central and north Florida during the cool months. Bahiagrass is a low-maintenance choice with a deep root system that tolerates drought. Zoysiagrass is suitable for all areas of the state, and centipedegrass and bermudagrass are also used.

UF/IFAS names bahiagrass and bermudagrass as the best choices for starting from seed. St. Augustinegrass and zoysiagrass go in as sod or plugs. Bahiagrass can be planted at any time of year in much of the state, but spring or early summer is best in north Florida.

Frost dates from NOAA

Dates are the NOAA 1991-2020 normals for the last spring and first fall 32 F freeze at 50% probability. At Pensacola Regional Airport the average last spring frost is February 14 and the average first fall frost is December 9. At Tallahassee the dates are March 11 and November 21, and at Jacksonville February 25 and December 7.

Orlando International lists January 25 and January 10, and Tampa International lists January 20 and January 12. Each pair falls within January, so a freeze there, when it comes, is a midwinter event and does not mark the edge of a spring or fall season. NOAA publishes no 32 F date for Miami International.

Spring

Spring feeding starts after frost danger is past and temperatures stay warm. Choose a fertilizer for your grass type, with slow-release nitrogen and little or no phosphorus, since many Florida soils already hold plenty.

Spring is also the time to treat chinch bugs on St. Augustinegrass if you confirm them, since injury shows as yellow to brown patches that start in water-stressed or full-sun grass. Seeding bahiagrass or bermudagrass fits April to July, which leaves a full growing season before cold weather.

Summer

Mow at the high end of the range. UF/IFAS lists bahiagrass at 3.5 to 4 inches, standard St. Augustinegrass at 3.5 to 4 inches, semidwarf St. Augustinegrass at 2 to 2.5 inches, centipedegrass at 1 to 2 inches and most zoysiagrass at 1.5 to 2 inches. Never remove more than a third of the blade at once.

Water when the lawn shows folded blades, a blue-gray color or lasting footprints. During active growth that usually means once or twice a week, applying one half to three quarters of an inch each time, with the larger amount for sandy south Florida soils. Water around sunrise. Water management district rules override this advice, and many counties and cities have fertilizer ordinances, so ask your county Extension office.

Fall

Make the last feeding by the end of September in north Florida and mid-October in central Florida, using a high-potassium fertilizer if you can. Feeding later keeps the grass growing when cold weather arrives and makes it more cold-sensitive. If you miss the fall feeding, UF/IFAS says to feed in spring as growth starts.

Centipedegrass and St. Augustinegrass are prone to large patch fungus in fall, so avoid extra nitrogen and water early in the day. Scout for sod webworms. For a green winter lawn in north or central Florida, sow ryegrass once daytime highs fall to the low to mid 70s, after raking and mowing, and keep it watered until it sprouts.

UF/IFAS Extension and soil testing

UF/IFAS Extension's Gardening Solutions site covers lawns, and every county has an Extension office that can give current local advice. A soil test shows whether the lawn needs anything beyond nitrogen.

You can send a sample to the UF/IFAS Soil Testing Laboratory or use the SoilKit test, both available through your county Extension office. SoilKit results also account for local fertilizer ordinances.