Material planning guide
Grass Seed Rates: New Lawn vs Overseeding
The same seed product can list different coverage for establishing a lawn and overseeding existing grass. Select the task on the label before turning bag coverage into an application amount.
Reviewed September 6, 2026Convert bag coverage into a rate
Rate in lb per 1,000 ft² = bag weight ÷ stated coverage × 1,000. A hypothetical 10 lb bag covering 2,000 ft² corresponds to 5 lb per 1,000 ft². If its alternate task coverage were 4,000 ft², that rate would be 2.5 lb.
Illustrative rates for a 10 lb bag
Use the coverage printed on your own blend, not these examples.
| Label coverage | Equivalent rate |
|---|---|
| 1,000 ft² | 10 lb / 1,000 ft² |
| 2,000 ft² | 5 lb / 1,000 ft² |
| 4,000 ft² | 2.5 lb / 1,000 ft² |
Calculate only the area receiving seed
For 3,200 ft² at an entered 5 lb per 1,000 ft², the required seed is 16 lb. Two 10 lb bags supply 20 lb, leaving 4 lb unused. The purchase quantity does not change the application rate.
Keep product and task matched
The Pennington reference demonstrates distinct new-lawn and overseeding coverage on one product. That distinction cannot be transferred blindly to another blend. Also check whether the package weight includes coatings or other ingredients and follow the product’s own application instructions.
Sources and product references
- Pennington — Smart Seed Sun and Shade
Example of product-specific coverage that differs between new seeding and overseeding.
- NIST — SI units: volume
Unit relationships; supplier product coverage and prices remain separate inputs.