Grass Seed Calculator: How Much Seed Do I Need
Work out how much grass seed to buy. Enter your lawn area, then pick a new lawn or overseeding rate, or set your own rate from the seed bag label.
How to calculate grass seed
- Enter the lawn area in square feet.
- Choose new lawn or overseeding, or type the rate from the seed bag.
- Read off the pounds of seed to buy.
Examples
5000 sq ft new lawn at 5 lb per 1000
Area 5000, purpose new
25 lb of seed
Frequently asked questions
How much grass seed do I need per square foot?
Seeding rates are given per 1000 square feet. A new lawn typically needs about 5 lb per 1000 sq ft and overseeding an existing lawn needs about 2.5 lb per 1000 sq ft. Always check your seed bag, since rates vary by grass type.
What is the difference between new lawn and overseeding rates?
A new lawn starts from bare soil and needs full coverage, so it uses a heavier rate. Overseeding adds seed to thin areas of an existing lawn, so it uses about half as much.
Why does the rate differ by grass type?
Seeds vary in size and germination. Fine fescues and bluegrass have many small seeds per pound, while ryegrass seeds are larger, so the recommended pounds per 1000 sq ft change with the species.
Should I buy extra seed?
A small surplus helps. It covers uneven spreading, lets you patch any bare spots after germination, and keeps your spreader topped up so you do not run out mid lawn.
When is the best time to seed a lawn?
Early fall is ideal for cool season grasses, with late spring as a second choice. Warm season grasses do best in late spring to early summer when the soil is warm.
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