How Much Grass Seed Do I Need? Rates per 1,000 sq ft

The formula

Every extension table on this page gives seed in pounds per 1,000 square feet. So the amount for your lawn is:

That leaves two numbers to find: the area of the lawn and the rate for your grass. The rate is where the grasses differ most: from ½ pound to 8 pounds per 1,000 square feet in a single extension table. The next section has the rates.

Seeding rates by grass

University of Tennessee Extension publishes one table for the common lawn grasses. It explains why the numbers are so far apart: seed size and viability set the rate. Small-seeded grasses such as Kentucky bluegrass and bermudagrass need fewer pounds per 1,000 square feet than grasses with large seed, such as perennial ryegrass and tall fescue.

Notes from the same publication:

• Bermudagrass: the rate is for hulled seed. Double it when you use unhulled seed, which also often takes 14 to 21 days or longer to germinate.
• Cool-season grasses (bluegrass, fescues, ryegrasses) germinate fastest when the air cycles between about 59 and 82 °F. Warm-season grasses (bermudagrass, centipedegrass, zoysia) usually germinate well at 68 to 95 °F.
• Slow starters: bermudagrass, centipedegrass, Kentucky bluegrass and zoysia usually take longer to come up than the fescues and ryegrasses. A bluegrass lawn that looks bare after a week is not necessarily a failure.
• Too much seed: planting too much most often gives a very dense stand of weak, poorly developed and disease-prone seedlings. More seed is not a safety margin.

Other extension services publish their own numbers for their region, and they do not always match. NC State Extension, for example, gives ¼ to ½ pound of centipedegrass seed per 1,000 square feet, the low end of Tennessee's range, and 1 to 2 pounds of common bermudagrass seed. Tall fescue runs from 5 to 8 pounds in Tennessee to 6 to 9 pounds in Purdue's table. If your state's extension service has a rate, use it; it was written for your climate.

Blends and mixtures

Many bags hold more than one grass. As the table shows, a mixture's rate falls between the rates of the grasses in it. Purdue Extension and University of Illinois Extension give these rates for lawns in Indiana and Illinois:

The label lists the share of each grass in a mixture, so you can match a bag to the closest row. The label section below shows where to read it.

New lawn or overseeding?

Seeding bare soil and thickening a lawn that already has grass are different jobs, and the extension services do not agree on one overseeding rate:

• Kansas State University gives 6 to 8 pounds of tall fescue per 1,000 square feet for new areas and "about half as much" for overseeding. For Kentucky bluegrass it gives 2 to 3 pounds for a new lawn and half that for overseeding.
• NC State Extension overseeds thin, bare areas of a tall fescue lawn with 6 pounds of turf-type tall fescue per 1,000 square feet, a full new-lawn rate.
• Purdue says the overseeding rate for Kentucky bluegrass is the same as bare-ground seeding, 2 to 3 pounds per 1,000 square feet.

The sources do not say which of these rates fits which lawn, so the worked example below shows both. All of them give the rate per 1,000 square feet of ground to be seeded, so measure the area you actually seed. For advice that fits your grass and region, ask your local extension office.

Seed only works where it reaches the soil. Purdue rakes lightly and rolls after seeding for good seed-to-soil contact, and Kansas State mows short, removes the clippings and core-aerates in several passes before overseeding tall fescue so the seed has holes to fall into.

When to seed

The right window depends on the grass and on where you live, so here is only what each source says for its own region:

• Cool-season grasses in Indiana and Illinois (Purdue): late summer to early fall is best. August 15 to September 15 in the northern half of both states, September 1 to 30 in the southern half. Seed as early in the window as you can: waiting one week may add 2 to 4 weeks before the stand matures.
• Spring and summer there: spring seeding is "difficult and often unsuccessful", and summer seeding should be avoided because the seedlings lose to heat, drought and summer weeds. When spring seeding cannot be avoided, Purdue suggests dormant seeding before the ground thaws, from as early as Thanksgiving to as late as March, depending on the location.
• Tall fescue in North Carolina (NC State): overseed thin areas as the weather cools, August 15 to September 1 in the western region and September 1 to October 1 in the piedmont and coastal plain.
• Warm-season grasses in North Carolina (NC State): start replanting bermudagrass in late May. Replant bare centipedegrass areas in May, or when daytime temperatures stay above 60 °F. Centipedegrass seed takes about 28 days to germinate, and a new centipedegrass lawn can take up to three years to establish.

Outside these states, ask your local extension office. Extension is run by state universities together with the U.S. Department of Agriculture and county governments, as the Tennessee and Arkansas publications note, and the Arkansas sheet points readers to the local county extension office for more. That office can tell you which grass, which rate and which weeks suit your area.

Measure the lawn, not the lot

The area in the formula is the area you will actually seed. Subtract the house, the driveway, the patio, paths and planting beds; a lot size from a deed or a listing is far too large. For overseeding, measure only the part that needs it.

The quick way: sketch the yard, split the lawn into rectangles, triangles and circles, measure each and add them up, then subtract the beds and paving inside them. The square footage calculator does the shapes and the adding for you, and its formulas section shows each one. The guide on how to measure a room covers measuring habits that work outdoors too, starting with one sketch that holds every number.

If your plan or tape is in meters, convert the area with the area converter, or use the grams-per-square-meter column in the rate table and stay metric throughout.

Worked example: one yard

A yard with a front lawn of 50 by 30 feet and a back lawn of 60 by 45 feet. The back lawn has a 16 by 12 foot patio and a round tree bed with a 4-foot radius, both of which get no seed.

That is 368 square meters, and 3.958 units of 1,000 square feet. Now the seed, at University of Tennessee's rates for a new lawn:

The same yard needs 3.3 to 4 times as much tall fescue as bluegrass by weight. That is the seed-size difference from the rate table, not a difference in how much lawn you get.

Rounding up to bags

Seed is sold by the bag, so round up. The bag sizes below are examples to show the rounding, not standard sizes; use the net weight printed on the bags you can buy.

Leftover seed is not wasted if you keep it for patching, but the Arkansas seed tag sheet notes that germination often declines quickly in storage, so old seed is not as good as the label says. For bags labeled in kilograms, the weight converter turns them into pounds.

Overseeding only the back lawn

Now say only the back lawn (2,458 square feet after the patio and bed) has thinned out and gets tall fescue:

• At Kansas State's half rate, 3 to 4 pounds per 1,000 square feet: 7.4 to 9.8 pounds.
• At NC State's 6 pounds per 1,000 square feet for thin, bare areas: 14.7 pounds.

The gap between the two is the judgment call from the overseeding section: the barer the ground, the closer you go to the higher number.

Reading the seed label

Federal and state seed laws require seed companies to test seed lots for purity, germination and weed contamination and to report the identity and origin of the seed. That is what the tag or printed label on the bag shows. The University of Arkansas fact sheet on reading seed tags, written for farm seed but covering the same items, explains each one. Its first advice: do not buy seed without a seed tag.

Pure live seed: comparing two bags

Pure seed and germination together tell you how much of the bag can actually grow. The Arkansas sheet calls it pure live seed (PLS): percent purity times percent germination. Two example labels on bags of the same net weight:

Bag B weighs the same but holds 1.60 pounds less seed that can grow. A heavy coating counts as inert matter, which is one reason a bag can have low purity. The sheet adds that the same calculation compares seed lots for cost, for example by dividing each price by the pounds of live seed instead of the net weight.

The sheet also shows how to adjust a rate for a weak seed lot: divide the recommended rate by the PLS. For bag B and a 6-pound rate, that is 6 ÷ 0.7225 = 8.3 pounds. The adjusted rate is always higher than the recommended one. The sheet uses it for farm seed lots with low germination (below 75%) or poor purity; for a lawn, choosing a better bag is the simpler fix.

Spread it evenly

The right amount only helps if it lands evenly. Purdue prefers a drop spreader, because rotary spreaders do not spread seed uniformly. Its method: set the spreader very low, sow half of the seed in one direction, then the other half at right angles to the first. It may take three or more passes in each direction, which Purdue calls "well worth the time". Afterward, rake lightly and roll lightly so the seed touches the soil. For the starter fertilizer, mulching and watering that follow, your extension service's establishment guide has the details for your area; the Purdue and Tennessee publications in the sources cover them.

Plan the lawn with the beds

If you are laying out a new lawn together with planting beds, sketch both on one plan before you buy anything. The free garden planner has a grid for drawing the beds, and the same sketch gives you the lawn pieces to measure. Write the grass, the rate from your extension service and the seeding window next to it, and the order list follows from the formula at the top of this page.

Frequently asked questions

Sources

• Samples and Sorochan, Turfgrass Establishment: Seeding, University of Tennessee Extension publication W160-B (2007): recommended seeding rates in pounds per 1,000 square feet and days to germinate for eight turfgrasses, doubled rate for unhulled bermudagrass, germination temperatures, the effect of too much seed
• Reicher, Bigelow, Patton and Voigt, Establishing Turfgrass Areas From Seed, Purdue Extension and University of Illinois Extension publication AY-3-W (revised May 2006): seeding windows for Indiana and Illinois, dormant and summer seeding, spreading seed in two directions, Table 2 seeding rates for blends and mixtures
• Hardebeck, Dormant Overseeding, Purdue University Plant and Pest Diagnostic Laboratory, Picture of the Week (December 7, 2020): overseeding rate for Kentucky bluegrass equal to bare-ground seeding, 2 to 3 lb per 1,000 sq ft; dormant seeding after Thanksgiving through early March
• Kansas State University, Fall Turfgrass Recommendations and Tips, K-State Turf news (August 27, 2019, tips by Ward Upham): tall fescue 6 to 8 lb per 1,000 sq ft for new areas and about half for overseeding; Kentucky bluegrass 2 to 3 lb for a new lawn and half for overseeding
• Miller, Yelverton, Peacock, Kerns, Brandenburg and Billeisen, Tall Fescue Lawn Maintenance Calendar, NC State Extension publication AG-367 (July 8, 2021): overseeding windows by region and 6 lb of turf-type tall fescue per 1,000 sq ft
• Miller, Kerns, Billeisen, Yelverton, Peacock and Brandenburg, Bermudagrass Lawn Maintenance Calendar, NC State Extension publication AG-431 (July 30, 2021): replanting from late May, common bermudagrass seed at 1 to 2 lb per 1,000 sq ft
• Miller, Martin, Kerns, Yelverton, Brandenburg and Billeisen, Centipedegrass Lawn Maintenance Calendar, NC State Extension publication AG-381 (August 4, 2021): replanting in May, seed at ¼ to ½ lb per 1,000 sq ft, 28 days to germinate, up to three years to establish
• Kubesch, Philipp, Simon and Dick, How to Read a Seed Tag, University of Arkansas System Division of Agriculture fact sheet FSA3163 (2025): seed tag items, test date, pure live seed formula and adjusted seeding rate

Written by Tobias. Updated October 22, 2026.