Miscellaneous
Grass Seed Calculator - Coverage by Grass Type
Calculate how much grass seed you need for a new lawn or overseeding. Coverage rates differ for new lawns vs. overseeding and by grass variety.
Seeding rates by grass type
| Grass type | New lawn (lbs/1,000 sq ft) | Overseeding (lbs/1,000 sq ft) |
|---|---|---|
| Kentucky Bluegrass | 2–3 | 1–2 |
| Tall Fescue | 6–8 | 3–4 |
| Perennial Ryegrass | 6–8 | 3–4 |
| Bermuda (hulled) | 1–2 | 0.5–1 |
| Zoysia (plugs) | N/A - plugs/sod | N/A |
Best time to seed
- Cool-season grasses (fescue, ryegrass, bluegrass): late summer to early fall (soil temp 50–65°F). Spring is second-best.
- Warm-season grasses (Bermuda, Zoysia, St. Augustine): late spring to early summer (soil temp 65–70°F).
New seeding vs. overseeding
New lawn seeding uses the full seed rate listed in the table above. Overseeding an existing lawn uses roughly half the rate because established grass provides competition and the bare soil percentage is lower. Scalping the existing lawn to 1–12 inch and aerating first significantly improves overseeding results.
Soil preparation steps
- Aerate or dethatch existing lawn (for overseeding) or till to 4–6 inches (for new lawn).
- Add 2–3 inches of topsoil or compost and till in.
- Rake to a smooth, firm seedbed - seed–soil contact is critical.
- Seed using a broadcast or drop spreader in two perpendicular passes for even coverage.
- Lightly rake seed into the top ‘⁄₄ inch of soil; do not bury seed deeply.
- Apply starter fertilizer (high phosphorus, e.g. 24-25-4).
Watering schedule
- Until germination: water lightly 2–3 times per day to keep the top ‘⁄₄ inch moist. Avoid saturating.
- After germination: transition to deeper, less frequent watering (1 inch per week) to encourage deep root growth.
- First mowing: wait until grass reaches 3–4 inches before first mow; do not mow below 2½ inches.