How Much Grass Seed Do I Need?
Seed is applied by rate — pounds per 1,000 square feet — so you need two numbers: your lawn's area and the right rate for the job. Establishing a brand-new lawn from bare soil takes roughly twice the seed of thickening an existing one, because you're aiming for full coverage rather than filling gaps. The calculator multiplies your area by the rate you choose and gives pounds.
New lawn vs. overseeding
For a new cool-season lawn, about 5 pounds per 1,000 square feet is typical; for overseeding a thin but living lawn, around 2.5 is plenty. Warm-season grasses and specialty blends differ, so the number on your seed bag always wins over a general rule. Applying far more than the recommended rate doesn't help — crowded seedlings compete and thin themselves out.
Spreading evenly
Even coverage matters more than exact quantity. Split your seed into two halves and spread one half walking north-south and the other east-west; the crosshatch pattern prevents the stripes and bare patches you get from a single pass. Buy about 10% extra for edges, reseeding misses, and the birds. Water lightly and often until germination, then taper off.
Frequently asked questions
- How much seed for a new lawn?
- About 5 pounds per 1,000 square feet for most cool-season blends — double the overseeding rate.
- Can I use too much grass seed?
- Yes. Overcrowded seedlings compete for water and light and thin themselves out, wasting seed.
- Which way should I spread it?
- Split the seed and spread half in each direction, crosshatched, for even coverage without stripes.