Bags of mulch by bed size
Number of 2 cu ft bags needed, rounded up, and cubic yards at 3 inches.
| Bed area | 2 in deep | 3 in deep | 4 in deep | Cu yd at 3 in |
|---|---|---|---|---|
| 50 sq ft | 5 | 7 | 9 | 0.46 |
| 100 sq ft | 9 | 13 | 17 | 0.93 |
| 200 sq ft | 17 | 25 | 34 | 1.85 |
| 300 sq ft | 25 | 38 | 50 | 2.78 |
| 500 sq ft | 42 | 63 | 84 | 4.63 |
| 1,000 sq ft | 84 | 125 | 167 | 9.26 |
How the mulch calculator works
Cubic feet = Σ (length × width) × depth (in) ÷ 12 × (1 + extra %)
Bags = cubic feet ÷ bag size, rounded up
Cubic yards = cubic feet ÷ 27
Bulk cost = cubic yards × price per yard + delivery
Example
Two beds of 20 × 4 ft and 10 × 6 ft make 140 sq ft. At 3 inches that is 35 cubic feet: 18 bags of 2 cu ft mulch, or 1.30 cubic yards in bulk.
When bulk beats bags
Bulk has a fixed delivery fee, so it only pays off once you need enough material to spread that fee thin. The calculator finds the break-even point from the prices in the cost table: below it, buy bags; above it, order a load. Topsoil usually crosses over much sooner than mulch because bagged topsoil costs more per yard.
Don't pile it on
More is not better. Clemson Extension warns that excessive amounts of fine-textured mulch can suffocate plant roots, and advises keeping mulch 2 to 3 inches away from the stems of woody plants to prevent decay and rodent damage. Refresh a thin old layer rather than adding the full depth on top every year.
Frequently asked questions
How many bags of mulch do I need?
Multiply the bed area in square feet by the depth in inches and divide by 12 to get cubic feet, then divide by the bag size. For 200 sq ft at 3 inches: 200 × 3 ÷ 12 = 50 cubic feet, or 25 bags of 2 cu ft mulch.
How deep should mulch be?
Most wood and bark mulches work best at 2–3 inches. Clemson Extension says wood and bark mulches should not be more than 2 to 3 inches deep, with coarse pine bark nuggets up to 4 inches; Iowa State suggests 3–4 inches of wood chips on well-drained sites and 2–3 inches on heavy soils. Keep mulch pulled back from tree trunks and stems.
How many bags of mulch are in a yard?
A cubic yard is 27 cubic feet, so it takes 13.5 bags of 2 cu ft mulch — buy 14 — or 18 bags of 1.5 cu ft mulch.
Is bulk mulch cheaper than bags?
Not always. At the prices on this page a 2 cu ft bag averages $3.47, which is about $47 per cubic yard, while bulk mulch runs $25–$100 per yard plus a $50–$150 delivery fee. Cheap bagged mulch often wins on price for small and medium beds; bulk saves you hauling and opening dozens of bags. The calculator shows the break-even point for your own prices.
How much topsoil do I need?
Use the same area × depth math: 100 sq ft at 4 inches is 33.3 cubic feet, or 1.23 cubic yards. Bagged topsoil averages $2.87 per 1 cu ft bag, so beyond a yard or two a bulk load (about $10–$55 per yard plus delivery) is usually cheaper.
Sources
Prices are national shelf prices and cost-guide ranges read on September 17, 2026. The calculator uses the typical price (the median of the shelf prices we saw) and shows the low–high range; type your own local price to update the total.
All sources for this page (9)
Coverage, yield and building specs
- Clemson Cooperative Extension HGIC — Mulch accessed 2026-09-16
- Iowa State University Extension — How deep should mulch be? accessed 2026-09-16
Prices
- The Home Depot — Vigoro mulch accessed 2026-09-16
- The Home Depot — Mulch category accessed 2026-09-16
- HomeGuide — Mulch prices accessed 2026-09-16
- Angi — Topsoil cost accessed 2026-09-16
- The Home Depot — Garden soil, top soil accessed 2026-09-16
- The Home Depot — Topsoil accessed 2026-09-16
- HomeGuide — Fill dirt, sand & topsoil cost accessed 2026-09-16
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