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
- 6 inches minimum — playgrounds (CPSC requirement)
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 (about 8–9 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.