How much mulch do I need?
Multiply the bed's area by the depth you want, then convert to cubic yards. Bulk mulch is sold by the cubic yard. Bags are sold by the cubic foot.
Cubic yards = length (ft) × width (ft) × depth (in) ÷ 324
A 20 ft × 6 ft bed at 3 inches deep: 20 × 6 × 3 ÷ 324 = 1.11 cubic yards. Add 10% for settling and you'd order 1.25 yards, or 17 two-cubic-foot bags.
The calculator above does this for every bed at once, including round beds (area = 3.14 × radius²) and triangular corners (area = base × height ÷ 2).
Mulch calculator by square feet
Already know the area? Pick "I know sq ft" on any bed above. Or use this table: cubic yards needed per 100 sq ft.
| Depth | Per 100 sq ft | Per 500 sq ft | Per 1,000 sq ft |
|---|---|---|---|
| 2 in | 0.62 yd | 3.1 yd | 6.2 yd |
| 3 in | 0.93 yd | 4.6 yd | 9.3 yd |
| 4 in | 1.23 yd | 6.2 yd | 12.3 yd |
How deep should mulch be?
| Where | Depth | Why |
|---|---|---|
| Flower and shrub beds | 2–3 in | Blocks weeds without smothering roots |
| Around trees | 2–4 in | Keep it 3 in away from the trunk |
| Paths | 3–4 in | Holds up to foot traffic |
| Rubber mulch, beds | 1.5–2 in | It doesn't break down, so less goes further |
| Playgrounds, wood fiber | 9–12 in | Fall protection under play equipment |
| Playgrounds, rubber | 6 in | Fall protection with less material |
Rubber mulch and playground mulch
Rubber mulch doesn't break down, so beds only need 1.5–2 inches. Under play equipment, plan on 6 inches of rubber mulch or 9–12 inches of engineered wood fiber for fall protection. Rubber mulch is usually sold in 0.8 cu ft bags, so you'll need about 34 bags per cubic yard.
Bags or bulk?
One cubic yard is 27 cubic feet. Bags usually win under about 2 yards. Above that, bulk delivery is cheaper even with the delivery fee. The calculator compares both using your prices.
| Cubic yards | 2 cu ft bags | 3 cu ft bags | Covers at 3 in |
|---|---|---|---|
| 1 | 14 | 9 | 108 sq ft |
| 2 | 27 | 18 | 216 sq ft |
| 3 | 41 | 27 | 324 sq ft |
| 5 | 68 | 45 | 540 sq ft |
| 10 | 135 | 90 | 1,080 sq ft |
Mulch bags at Home Depot and Lowe's
Big-box stores mostly sell mulch in 2 cu ft bags, with some 1.5 and 3 cu ft bags. Set the bag size in the calculator to match the bag on the shelf. A full pallet usually holds 60–65 two-cubic-foot bags, which is about 4.5 cubic yards, so if your result is near that, ask about pallet pricing or bulk delivery.
Pricing a mulch job
Most landscapers price mulch installs as material plus markup, plus labor at roughly 1 to 2 cubic yards per crew-hour, depending on wheelbarrow distance. Switch the calculator to contractor mode to price the job that way and turn the result into an itemized estimate, or start from the landscaping estimate template.
Questions
How many bags of mulch are in a yard?
13.5 two-cubic-foot bags or 9 three-cubic-foot bags make one cubic yard.
How much does a yard of mulch cover?
About 108 sq ft at 3 inches deep, 162 sq ft at 2 inches, and 81 sq ft at 4 inches.
How much rubber mulch do I need for a playground?
Plan on 6 inches of rubber mulch under play equipment. Pick "Rubber mulch" above and use the 6 in depth; the bag count uses 0.8 cu ft rubber bags.
Should I remove old mulch first?
If the old layer is more than 2 inches thick or matted, rake it out or break it up. Otherwise just top it up, and reduce the depth you enter by what's still there.