Seed Needed
15–20 lbs
Rate
3–4 lbs/1000 sqft
Est. Cost
$55–$70
Existing lawn — uses reduced overseeding rate
Average US lawn is 5,000–10,000 sq ft
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Inputs
Result
Tall fescue overseeding rate = 3–4 lbs/1,000 sq ft. For 5,000 sq ft: 5 × 3 = 15 lbs (low) and 5 × 4 = 20 lbs (high). Average = 17.5 lbs, needing 2 ten-pound bags.
Inputs
Result
Kentucky bluegrass new lawn rate = 2–3 lbs/1,000 sq ft. For 10,000 sq ft: 10 × 2 = 20 lbs (low) and 10 × 3 = 30 lbs (high). At ~$6/lb, seed costs $120–$180 plus $20 for fertilizer.
Inputs
Result
Bermuda overseeding rate = 0.5–1 lb/1,000 sq ft. For 3,000 sq ft: 3 × 0.5 = 1.5 lbs (low) and 3 × 1 = 3 lbs (high). Bermuda seed is more expensive at ~$8/lb but requires much less quantity.
Seed rates vary by grass type and whether you are starting a new lawn or overseeding. Kentucky bluegrass needs 2–3 lbs/1,000 sq ft for new lawns and 1–2 lbs for overseeding. Tall fescue needs 6–8 lbs new and 3–4 lbs for overseeding.
| Grass Type | New Lawn | Overseed | Season |
|---|---|---|---|
| Kentucky Bluegrass | 2–3 lbs | 1–2 lbs | Cool |
| Tall Fescue | 6–8 lbs | 3–4 lbs | Cool |
| Perennial Ryegrass | 8–10 lbs | 4–5 lbs | Cool |
| Bermuda | 1–2 lbs | 0.5–1 lb | Warm |
| Zoysia | 1–2 lbs | 0.5–1 lb | Warm |
Cool-season grasses (bluegrass, fescue, ryegrass) do best when overseeded in late August through mid-October. Warm-season grasses (bermuda, zoysia) should be overseeded from late April through June. Soil temperature should be 50–65°F for cool-season and 65–80°F for warm-season.
Overseeding spreads new seed over existing grass to fill thin spots without removing the old lawn. Reseeding (or renovation) involves killing or removing existing grass before starting fresh. Overseeding uses about half the seed rate of a new lawn installation.
Yes, apply a starter fertilizer high in phosphorus (like 18-24-12) at the time of seeding. Phosphorus promotes root development in new seedlings. Apply about 1 lb of nitrogen per 1,000 sq ft. Avoid weed-and-feed products, as pre-emergent herbicides prevent grass seed from germinating.
Germination time varies by grass type. Perennial ryegrass is fastest at 5–10 days. Kentucky bluegrass is slowest at 14–28 days. Bermuda takes 10–30 days. Keep the soil consistently moist during the germination period for best results.
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Last Updated: Mar 16, 2026
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