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A new lawn’s first few mowings decide how well it fills in. Seeded grass is usually ready once it’s a third taller than its normal mowing height; new sod once it has rooted and doesn’t lift when tugged. To start it right, get a new-lawn quote from a local pro. Part of lawn mowing cost and hiring.
01 / Guides
- Mowing a new lawn: when it’s ready for the first cut Seed and sod timelines.
02 / Best planting windows for grass seed and sod
Seed germinates when the soil is warm enough for that type of grass, so the calendar date matters less than soil temperature. Oklahoma State University Extension gives these windows, with Oklahoma dates as the example:
| Grass group | Soil-surface temperature | Best time (Oklahoma example) | Notes |
|---|---|---|---|
| Warm-season (bermuda, zoysia) | Averaging 68–95°F | Not before May 1; seed most bermudagrasses by July 1 | Gives the grass the summer to establish |
| Cool-season (tall fescue, Kentucky bluegrass, perennial ryegrass) | 68–86°F for best germination | Late September–October | March is second best |
For cool-season lawns, OSU says fall plantings beat spring plantings because the roots develop before summer heat arrives. A March seeding has only a few months to root before it faces its first hot, dry stretch. If you’re starting a fescue or bluegrass lawn, fall is worth waiting for.
03 / Sod or plug warm-season grass before the first frost
Sod, plugs and sprigs need time to root before cold weather. Oklahoma State University Extension recommends laying warm-season sod at least one month before the first fall frost, and plugging or sprigging at least two months before. Plugs and sprigs need the extra time because they have to spread to cover the soil.
Here is how that rule works out using NOAA’s 1991–2020 climate normals. In a typical year (median), the first fall 32°F night in Dallas–Fort Worth is around November 24, so sod should go down by about late October.
| City | First fall 32°F (median) | Sod: plan to finish by about | Plugs or sprigs: plan to finish by about |
|---|---|---|---|
| Dallas–Fort Worth, TX | Nov 24 | Oct 24 | Sep 24 |
| Atlanta, GA | Nov 20 | Oct 20 | Sep 20 |
| Tulsa, OK | Nov 4 | Oct 4 | Sep 4 |
| Oklahoma City, OK | Nov 2 | Oct 2 | Sep 2 |
These are median dates, so treat the deadlines as targets rather than guarantees and give yourself extra margin if your yard sits in a low, cold spot.
04 / Grass seeding rates per 1,000 square feet
Seeding rates are given in pure live seed (PLS), the part of the bag that is viable seed of the grass you’re buying. Oklahoma State University Extension lists these rates for a new lawn:
| Grass | Season | Growth habit | Seeding rate (PLS per 1,000 sq ft) |
|---|---|---|---|
| Kentucky bluegrass | Cool | Spreads by rhizomes | 2 lb |
| Perennial ryegrass | Cool | Not listed | 4–8 lb |
| Tall fescue | Cool | Bunch-type | 4–6 lb |
| Bermudagrass (seeded) | Warm | Stolons and rhizomes | 1–2 lb |
Growth habit explains part of the spread in rates. Tall fescue is a bunch-type grass that doesn’t spread sideways much, so it needs enough seed to fill in on its own. Kentucky bluegrass spreads by rhizomes and bermudagrass by stolons and rhizomes, so they knit together from a lighter seeding.
05 / Caring for new grass until the first mow
- Keep the top inch moist. Oklahoma State University Extension recommends daily light watering for at least 10–14 days after seeding, then a shift to deeper, less frequent watering.
- Mow as soon as it’s needed. OSU Extension says to start mowing new turf as soon as it reaches its intended cutting height; in practice that means the first cut comes when the grass is about a third taller than that height, so the first pass takes off no more than a third. Mowing promptly promotes lateral spread and rooting.
- Hold off on weed killers. Avoid herbicides for the first 3–4 weeks after planting.
The first cut is the one most people get wrong, either waiting too long or scalping seedlings with a low deck. Mowing a new lawn walks through the seed and sod timelines in detail. If you’d rather not risk it, have a local crew handle the first mows while the new grass roots in.
New lawn going in?
A local pro can handle the first mowings so the new grass roots in well.
Frequently asked questions
When is the best time to plant grass seed?
It depends on the grass. Oklahoma State University Extension recommends seeding warm-season grasses once the soil surface averages 68–95°F, and cool-season grasses in late September through October, with March as the second-best time.
How late in the fall can I lay sod?
Oklahoma State University Extension recommends sodding warm-season grass at least one month before the first fall frost, and plugging or sprigging at least two months before.
How much grass seed do I need per 1,000 square feet?
Oklahoma State University Extension lists, in pure live seed per 1,000 sq ft: Kentucky bluegrass 2 lb, perennial ryegrass 4–8 lb, tall fescue 4–6 lb and seeded bermudagrass 1–2 lb.
How often should I water new grass seed?
Keep the top inch of soil moist with daily light watering for at least 10–14 days, then switch to deeper, less frequent watering.
When can I use weed killer on a new lawn?
Avoid herbicides for the first 3–4 weeks after planting, according to Oklahoma State University Extension.
Sources: NOAA U.S. Climate Normals (1991–2020); Oklahoma State University Extension, HLA-6419; NC State Extension Gardener Handbook; Penn State Plant Science.