Seed bare soil at the full rate and a thin existing lawn at roughly half. The University of Maryland Extension recommends 6 to 8 lb of turf-type tall fescue per 1,000 sq ft for a new lawn and 4 lb for overseeding; 2 to 3 lb of Kentucky bluegrass for a new lawn and 1.5 lb for overseeding; and 4 to 5 lb of fine fescue, or 2.5 lb for overseeding. Bluegrass seed is tiny, which is why its rate is so much lower.
The grass seed calculator applies these rates to your lawn size and bag size, or uses the rate on your seed label.
Seeding rates by grass
| Grass | New lawn, lb per 1,000 sq ft | Overseeding, lb per 1,000 sq ft |
|---|---|---|
| Turf-type tall fescue | 6 to 8 | 4 |
| Kentucky bluegrass | 2 to 3 | 1.5 |
| Fine fescue | 4 to 5 | 2.5 |
Purdue University lists 3 to 6 lb per 1,000 sq ft for the individual fine fescue species (creeping red, Chewings, hard and sheep fescue), in line with the Maryland figure.
Why overseeding uses less seed
An existing lawn already has plants; overseeding fills the gaps rather than starting from bare soil. Seeding at the full new-lawn rate into a living lawn crowds the seedlings and wastes seed. Aerating or slit seeding first puts the seed in contact with soil, which matters more than extra seed.
Worked examples
- New tall fescue lawn, 5,000 sq ft: at 7 lb per 1,000 sq ft (the middle of 6 to 8), 5 × 7 = 35 lb.
- Overseeding the same lawn with tall fescue: 5 × 4 = 20 lb.
- Overseeding 3,000 sq ft of Kentucky bluegrass: 3 × 1.5 = 4.5 lb.
Mixes and labels
Many bags are mixes, such as tall fescue with some bluegrass, and coated seed weighs more per seed than bare seed. For those, use the rate printed on the bag; the calculator has an option for it. Sow cool-season grasses in late summer to early fall where you can, and keep the soil surface moist until the seedlings are established.
Want grass faster? Compare with sod in sod rolls, slabs and pallets explained.
Seed for common lawn sizes
| Lawn | Tall fescue, new (7 lb) | Tall fescue, overseed (4 lb) | Kentucky bluegrass, new (2.5 lb) | Kentucky bluegrass, overseed (1.5 lb) |
|---|---|---|---|---|
| 1,000 sq ft | 7.0 lb | 4.0 lb | 2.5 lb | 1.5 lb |
| 2,500 sq ft | 17.5 lb | 10.0 lb | 6.2 lb | 3.8 lb |
| 5,000 sq ft | 35.0 lb | 20.0 lb | 12.5 lb | 7.5 lb |
| 10,000 sq ft | 70.0 lb | 40.0 lb | 25.0 lb | 15.0 lb |
Metric rates
One pound per 1,000 sq ft equals about 4.9 g per square meter. So 6 to 8 lb of tall fescue is about 29 to 39 g/m², and 2 to 3 lb of Kentucky bluegrass about 10 to 15 g/m².
Frequently asked questions
Should I use more seed to be safe?
No. Seeding well above the recommended rate crowds the seedlings so they compete for water and light and thin out later.
When should I overseed?
For cool-season lawns, late summer to early fall is the best time, when soil is warm and weeds are slowing down; spring is the second choice.
Do I need to cover the seed?
Rake it lightly into the soil so it makes good contact, and keep the surface moist until it germinates. Seed lying on top of thatch often fails.
Sources
- University of Maryland Extension: Lawn Establishment, Renovation, and Overseeding (HG 102) (seeding rates for new lawns and overseeding)
- Kansas State University: Fall Turfgrass Recommendations and Tips (tall fescue and bluegrass seeding rates, half rate for overseeding)
- Purdue University TURF-64-W: Establishment of Fine Fescues (fine fescue seeding rates by species)
