How Much Topsoil Do I Need?
Topsoil quantity depends on the area and the desired depth. Unlike mulch, topsoil is used for growing plants, so depth requirements are different — and topsoil is much heavier.
Standard Topsoil Depths
| Application | Depth | Why |
|---|---|---|
| Lawn top-dressing | 2-3" | Thin layer over existing grass; fills low spots |
| New garden beds | 6" | Standard root depth for vegetables and flowers |
| Raised beds | 12" | Deep root vegetables need 10-12" of soil |
| New lawn on poor soil | 4-6" | Provides growing medium before sod or seed |
Calculation
Volume (cu ft) = area × (depth ÷ 12)
For a 10 × 10 ft bed at 6" depth: 100 × (6 ÷ 12) = 50 cu ft = 1.85 cu yd.
Topsoil Weight
Topsoil is much heavier than mulch:
| Material | Density (lb/cu yd) | 1 cu yd covers (at 3") |
|---|---|---|
| Topsoil (moderately moist) | ~2,000 lb | 108 sq ft |
| Mulch | ~500-800 lb | 108 sq ft |
One cubic yard of topsoil weighs about 1 US ton. Plan delivery capacity — a standard pickup truck carries 1-2 cubic yards safely.
Bagged vs Bulk Topsoil
Bagged topsoil is typically 1 cu ft per bag or 40 lb bags (~0.75 cu ft). For beds under 2 cubic yards, bagged is convenient. For larger areas, bulk delivery is 50-70% cheaper.
Topsoil vs Mulch
Use topsoil when you need a growing medium (plants root into it). Use mulch when you need surface protection (weed suppression, moisture retention). See Topsoil vs Mulch: Which to Use for a detailed comparison.
Use the Calculator
The Topsoil Calculator handles volume, cubic yards, bags, and weight estimation. For mulch, use the Mulch Calculator.