Grass Seed Calculator
Enter the bare patch size, the seeding style - bare ground wants about 5 pounds per 1000 square feet, overseeding half that - and your seed price. The calculator gives pounds, cost, sprout timing and the first-mow rule.
Two rules decide patch success: seed-to-soil contact (rake it in so it stops being bird food) and twice-daily watering until sprouts show. The honest calendar note: spring seeding fights crabgrass pre-emergent, which kills grass seed as enthusiastically as weeds - you cannot have both the barrier and the patch.
How to use
- Measure the bare spots honestly - they always run bigger.
- Rake the seed in lightly; contact with soil is everything.
- Water twice a day, ten minutes, until the green shows.
Frequently asked questions
How much grass seed do I need per square foot?
Bare ground wants about 5 pounds per 1000 square feet; overseeding a thin lawn takes half that. The calculator scales the rate to your patch and prices it.
When should I plant grass seed?
Fall is the better season for cool-season grass on every measure - warm soil, cool air, fewer weeds. Spring works but competes with crabgrass pre-emergent, which kills grass seed along with the weeds: pick one.
How long does grass seed take to sprout?
Five to fourteen days depending on variety and warmth, with the first mow at three inches - about three to four weeks in. Daily watering until sprouts show is the non-negotiable part.
Why did my grass seed not grow?
Almost always seed-to-soil contact or water: seed sitting on top of old thatch is bird food, and a single missed day of watering at sprout time kills the crop. Rake in, water twice daily, and patience does the rest.