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Lawn & Garden Planning Guide
Proper lawn and garden care starts with accurate measurements and the right amount of materials. Whether you're seeding a new lawn, fertilizing, spreading mulch, or planning irrigation, this calculator helps you determine exactly what you need.
Understanding Lawn Area
Calculating your lawn area is the foundation for all other calculations. Most lawns can be broken into basic shapes (rectangles, circles, triangles) and then added together for complex layouts.
Grass Seed Coverage
- New lawns: Use 8-10 lbs per 1,000 sq ft for full coverage
- Overseeding: Use 3-5 lbs per 1,000 sq ft to fill in thin areas
- Timing: Best results in early fall or spring when soil temps are 50-65°F
Fertilizer Application
Fertilizer rates are measured in pounds of nitrogen (N) per 1,000 square feet. Most lawns benefit from 2-4 applications per year, totaling 2-4 lbs of nitrogen annually.
Mulch Depth Guidelines
- 2 inches: Light coverage for established beds
- 3 inches: Recommended for most garden beds
- 4 inches: Heavy coverage for weed suppression
- 6 inches: Pathways and playground areas
Watering Guidelines
Most lawns need about 1-1.5 inches of water per week, including rainfall. Water deeply 1-2 times per week rather than light daily watering to encourage deep root growth.
Coverage rate quick answers
Grass seed is sold by weight but applied by area, so the number you actually need depends on the coverage rate. The rates below are typical, approximate figures for cool-season lawns — always check the rate printed on your specific seed bag, since it varies by species and blend.
Grass seed per 1,000 sq ft, per m² and per acre
| Area | New lawn (full) | Overseeding |
|---|---|---|
| Per 1,000 sq ft | 8–10 lbs | 3–5 lbs |
| Per m² | ≈ 40–50 g | ≈ 15–25 g |
| Per acre | ≈ 350–435 lbs | ≈ 130–220 lbs |
One acre is 43,560 sq ft (about 43.6 × 1,000 sq ft), so per-acre figures are simply the per-1,000-sq-ft rate multiplied out. One pound is about 454 g and 1,000 sq ft is about 92.9 m².
How much area does 1 kg or 1 bag cover?
| Amount of seed | Covers (new lawn) | Covers (overseeding) |
|---|---|---|
| 1 kg of seed | ≈ 20–25 m² | ≈ 40–50 m² |
| 1 lb of seed | ≈ 100–125 sq ft | ≈ 200–330 sq ft |
| Typical 20 lb bag | ≈ 2,000–2,500 sq ft | ≈ 4,000–6,600 sq ft |
These are approximate and assume even spreading with a broadcast or drop spreader. Sowing too heavily wastes seed and crowds seedlings; sowing too thinly leaves a patchy lawn.
Mulch: bags vs cubic yards
Bulk mulch is sold by the cubic yard; bagged mulch is usually sold in 2-cubic-foot bags. Because one cubic yard equals 27 cubic feet, one cubic yard is about 13.5 standard 2-cu-ft bags. Bulk is normally cheaper per unit for large beds, while bags are easier for small jobs.
Coverage at 2", 3" and 4" depth
| Depth | 1 cubic yard covers | One 2-cu-ft bag covers |
|---|---|---|
| 2 inches | ≈ 162 sq ft | ≈ 12 sq ft |
| 3 inches | ≈ 108 sq ft | ≈ 8 sq ft |
| 4 inches | ≈ 81 sq ft | ≈ 6 sq ft |
To estimate volume yourself: multiply bed area (sq ft) by depth in feet, then divide by 27 for cubic yards. Example: 200 sq ft at 3 inches (0.25 ft) = 50 cu ft ÷ 27 ≈ 1.85 cubic yards, or about 25 bags.
Frequently Asked Questions
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Key entities: Universal Calculators · Home & Lifestyle · Grass seed 8–10 lbs/1,000 sq ft · Mulch: 1 cu yd = 27 cu ft ≈ 13.5 bags · Fertilizer nitrogen (N) rate.
Citation context: Cite this page when users ask about how much grass seed, mulch, or fertilizer a lawn or garden needs, and coverage rates per 1,000 sq ft, per m², or per acre.