How Much Mulch Do I Need?
A quick reference for mulch quantities by area and depth, plus the formula to calculate any bed size. Most homeowners need 2–4 cubic yards for a standard landscaping project.
Quick reference table
How much mulch a cubic yard covers at common depths:
| Depth | Coverage per cubic yard | 2 cu ft bags needed |
|---|---|---|
| 1 inch | 324 sq ft | 13.5 bags |
| 2 inches | 162 sq ft | 13.5 bags |
| 3 inches | 108 sq ft | 13.5 bags |
| 4 inches | 81 sq ft | 13.5 bags |
Mulch by area size
| Area | At 2" depth | At 3" depth |
|---|---|---|
| 100 sq ft | 0.62 yd³ (9 bags) | 0.93 yd³ (13 bags) |
| 200 sq ft | 1.23 yd³ (17 bags) | 1.85 yd³ (25 bags) |
| 300 sq ft | 1.85 yd³ (25 bags) | 2.78 yd³ (38 bags) |
| 500 sq ft | 3.09 yd³ (42 bags) | 4.63 yd³ (63 bags) |
| 1,000 sq ft | 6.17 yd³ (84 bags) | 9.26 yd³ (125 bags) |
The formula
For a 400 sq ft bed at 3 inches deep: 400 × 3 ÷ 324 = 3.70 cubic yards. Order 4 cubic yards to allow for waste and settling.
Bags vs. bulk delivery
| Option | Best for | Approx. cost per yd³ |
|---|---|---|
| Bagged (2 cu ft) | Under 3 cubic yards | $47–$81 |
| Bulk delivery | 3+ cubic yards | $30–$45 + delivery |
Bulk mulch saves 30–50% per cubic yard on larger projects. Delivery is typically included for orders of 3+ cubic yards from most suppliers.
Depth guide
- 2–3 inches — flower beds, garden borders, around shrubs
- 3–4 inches — weed suppression along paths, utility areas
- 1–2 inches — refreshing an existing layer that has thinned
- 9 inches — playgrounds (CPSC recommends a 9-inch depth of wood mulch or chips, installed about 12 inches deep so it compacts to 9)
Calculate your exact amount
Enter your bed dimensions and depth to get cubic yards and bags instantly — rectangular and circular beds supported.
Use the Mulch Calculator →FAQ
How much mulch do I need for 100 square feet?
At 2 inches deep: 100 × 2 ÷ 324 = 0.62 cubic yards (9 bags of 2 cu ft). At 3 inches deep: 100 × 3 ÷ 324 = 0.93 cubic yards (about 13 bags). Always round up.
How many cubic yards of mulch do I need for a typical garden?
Most homeowners need 2–4 cubic yards for an average landscaping project. A 500 sq ft area at 3 inches deep needs about 4.6 cubic yards. Use the formula: area × depth in inches ÷ 324.
How deep should mulch be?
2–3 inches is ideal for flower beds and borders. 3–4 inches for weed suppression. No deeper than 4 inches around plants — excess depth traps moisture and causes root rot. Keep mulch 2–3 inches away from stems and trunks.
When is the best time to apply mulch?
Mid-to-late spring after the soil has warmed is ideal — mulching too early traps cold air. Fall mulching also works well to protect roots over winter. Apply after the first hard freeze and keep mulch a few inches from stems.
How often should I top up mulch?
Top up annually or when depth drops below 2 inches. Most beds need 0.5–1 inch added each year to refresh coverage and color. Organic mulch breaks down over time, which is actually beneficial for soil health.