Loan Grass Seed Estimator
Seed is cheap; a thin lawn is expensive. Enter the area, pick the grass and say whether this is bare dirt or an overseed — get the pounds and bags at the rate that actually fills in.
Measure the lawn, not the lot: subtract the house, driveway, beds and patio. On a sloped or irregular lawn, break it into rectangles and add the areas.
How it works
Seed rates are set by seed size. One pound of Kentucky bluegrass holds roughly a million seeds, so a new bluegrass lawn needs only 3 lb per 1,000 sq ft; tall fescue seed is far larger, so the same coverage takes 8 lb; ryegrass 9, bermuda 2 (hulled), and a typical sun-and-shade blend 6. Overseeding rates are half the new-lawn rate — the existing turf fills the rest. The estimator multiplies your area by the rate for your grass and job, then rounds up to whole bags, because a half-bag short shows up as a thin stripe all season.
Method & worked example
Method: Pounds = lawn area ÷ 1,000 × the rate for the grass and job. New-lawn rates per 1,000 sq ft: bluegrass 3 lb, tall fescue 8, ryegrass 9, bermuda 2, sun-and-shade blend 6. Overseeding rates are roughly half. Bags round up to whole bags.
Worked example: A new 5,000 sq ft tall fescue lawn: 5 × 8 = 40 lb of seed — two 25-lb bags. The same area overseeded in bluegrass takes just 3 lb (2,000 sq ft takes 3.0 lb; scale by area).
When to use this
- You are starting a lawn from bare soil and buying seed by the bag.
- You are overseeding a thin lawn in fall and need the overseed rate, not the new-lawn rate.
- You are comparing seed quotes where one bid suspiciously uses half the pounds.
How to use it, step by step
- Measure the lawn area — subtract house, drive, beds and patio.
- Pick the grass type you are actually planting.
- Choose new lawn or overseed honestly — the rates differ by half.
- Order the bag count shown, not the raw pound count.
What the inputs mean
| Input | What it is | Typical values |
|---|---|---|
| Lawn area | Turf area in square feet | 2,000 sq ft patch job; 5,000–10,000 typical lawns |
| Grass type | Sets the seeding rate by seed size | Fescue 8 lb/1,000 new; bluegrass 3; bermuda 2 |
| Job type | New lawn (bare soil) or overseeding | Overseed rates ≈ half of new-lawn rates |
| Bag size | Retail bag weight for the round-up | 10, 25 and 50 lb bags are common |
Another worked example
Overseeding 2,000 sq ft of bluegrass in fall: rate 1.5 lb per 1,000 sq ft → 3.0 lb of seed, one 25-lb bag with plenty left for thin spots, about $10.50 of seed at $3.50/lb — overseeding is the cheapest lawn improvement there is when the rate is right.
Frequently asked questions
How much grass seed do I need for 5,000 sq ft?
For a new tall fescue lawn: 5 × 8 lb = 40 lb — two 25-lb bags. The same area in bluegrass takes just 15 lb. Overseeding that fescue lawn takes 20 lb. Grass type moves the answer more than any other input.
Is more seed better?
No. Over-seeding past the rate crowds seedlings into competition for water and light, and the stand comes up weaker and disease-prone. The rate on the tag is a ceiling as much as a floor — spend the extra money on watering instead.
When should I seed?
Cool-season grasses (bluegrass, fescue, ryegrass): early fall first, early spring second — soil warmth without weed pressure. Bermuda and other warm-season grasses go down in late spring once soil passes about 65°F.
Seed or sod?
Seed costs a tenth of sod per square foot but takes a season to look like a lawn; sod is instant and priced by the pallet. The Sod Estimator prices the instant route for the same area.
How long until a seeded lawn fills in?
Ryegrass germinates in 5–10 days, fescue in 7–14, bluegrass in a slow 14–30. A new lawn typically wants 8–12 weeks before real traffic, whatever the bag promises.
🌱 What will lawn care cost all season?
Seed down, the bills keep coming: mowing, fertiliser, cleanups. The Lawn Care Cost Estimator totals a full season of service for your lawn size.
Should I put down starter fertiliser with seed?
Yes for new lawns on tired soil — a starter formulation feeds the seedlings without burning them. The seed math here does not change; add the fertiliser as its own line in the budget.
How much watering does new seed need?
Light and frequent: keep the top half-inch of soil constantly moist until germination, which usually means 2–3 short waterings a day, then taper to deeper, rarer drinks as roots establish.