Seeding windows: cool-season vs warm-season grass, as extension pages give them
Extension pages put cool-season seeding in late summer and fall and warm-season seeding in late spring. Here is what each state's page actually says.
By LawnYear editorial team · Published · Updated Windows are read from the extension publications listed under Sources; the dates are approximate.
Approximate dates for your state. Check with your local cooperative extension office before you act.
The extension pages this site uses split into two groups by when they say to seed. None of them compares the two groups head to head, and none says which grass to grow.
For cool-season grasses, the sources point to late summer and fall. Virginia Cooperative Extension ranks August to October as the preferred seeding time and March to May as second best; its chart marks months rather than dates, so the exact days are approximate. Penn State Extension calls late summer the optimum time in most of Pennsylvania, meaning late August and early September, and does not suggest seeding later than mid-October. Ohio State's northeastern Ohio calendar says to seed by September 15 for fall establishment, and to wait until spring if it cannot be done by October 15. NC State gives August 15 to September 1 in the western region and September 1 to October 1 in the Piedmont and coastal plain for tall fescue. The University of Missouri says around mid-September, and the University of Georgia names October as the best month for tall fescue. Tennessee gives August 20 to September 15, and Purdue says August 15 to September 15 in central Indiana. Wisconsin names late August to early September, Kentucky mid-August to late September and Maryland late summer to mid-October. Rutgers gives August 20 to October 10 in southern New Jersey and August 15 to October 5 in the north.
For warm-season grasses, the windows that exist in these sources sit in late spring. The University of Georgia lists May to July as the best months to seed bermudagrass and centipedegrass and May and June for zoysiagrass, with April and August possible for bermudagrass, August for centipedegrass and April and July for zoysiagrass. The University of Missouri says to sprig, sod or seed warm-season grasses from mid-May to early June. Clemson says to replant large bare centipedegrass areas in May, using sod, seed or plugs. Kentucky says to establish bermudagrass and zoysiagrass in late May or June, once nights stay above 60 F, and Maryland plants zoysia in late May to early June.
Some sources also say what not to do. The University of Missouri says seeding cool-season grass in April or May is often a losing proposition because summer stress follows. Virginia and Ohio still list a spring window for cool-season grass, but both treat it as the lesser choice: Virginia ranks it second best, and Ohio calls fall the better season. Georgia lists February and March as possible, not best, for tall fescue.
Two warm-season grasses are special cases. The University of Georgia says St. Augustinegrass cannot be established from seed. The University of Missouri says the popular 'Meyer' zoysiagrass is not available as seed and is sodded, plugged or sprigged. So a seeding window does not exist for every warm-season grass.
The dates above differ inside each state. Your state's calendar is on its Lawn care page, or enter a ZIP code in the lawn schedule tool.
How we read the sources: where a post sets states or grasses side by side, the comparison is ours, made by reading the extension pages next to each other. Every number comes from the page named.