Mulch Calculator — Cubic Feet
Find how much mulch to buy. Depth defaults to 3 inches — the standard for new beds.
Recommended Mulch Depth
2 inches — annual refresh on existing mulched beds.
3 inches — new beds, standard application.
4 inches — heavy weed suppression, paths.
Never exceed 4 inches around trees and shrubs — it can suffocate roots and trap moisture against bark.
Types of Mulch
Hardwood bark: classic dark mulch, lasts 1–2 years, breaks down to enrich soil.
Cedar/cypress: more resistant to decay, naturally repels some insects.
Pine straw: lightweight, acidic — good for azaleas, rhododendrons, blueberries.
Wood chips: free from arborists; coarser, slower to decay.
Rubber mulch: doesn't decompose; common in playgrounds.
Bulk vs Bagged
Bagged mulch is convenient for small jobs and curbside drops. Bulk delivery is dramatically cheaper for anything over 5 cubic yards (about 68 bags). A standard pickup truck holds ~2 yd³; a single-axle dump truck delivers 4–7 yd³.
Coverage Table
| Cubic Yards | 2" deep | 3" deep | 4" deep |
|---|---|---|---|
| 1 | 162 sq ft | 108 sq ft | 81 sq ft |
| 2 | 324 sq ft | 216 sq ft | 162 sq ft |
| 3 | 486 sq ft | 324 sq ft | 243 sq ft |
| 5 | 810 sq ft | 540 sq ft | 405 sq ft |
| 10 | 1,620 sq ft | 1,080 sq ft | 810 sq ft |
Mulch vs Soil vs Gravel
All three landscaping materials use the same area × depth formula to reach cubic feet, but they serve different purposes and shouldn't be substituted for each other. Mulch sits on top of soil to retain moisture and block weeds — it does not replace soil as a planting medium. Gravel is for drainage, paths and driveways, not planting beds, since it doesn't retain water or break down into nutrients. If your project needs more than one material — for example, a bed with new topsoil topped with mulch — calculate each material's cubic feet separately with its own depth, since mulch depth (2–4 in) and soil depth (6–12 in) are rarely the same.
Frequently Asked Questions
How deep should mulch be?
2–4 inches deep. Less than 2 inches lets weeds through; more than 4 inches can suffocate plant roots.
How many bags of mulch in a cubic yard?
13.5 bags of 2 ft³, or 27 bags of 1 ft³.
How much area does a cubic yard of mulch cover?
At 3 inches deep, 1 cubic yard covers 108 square feet.
Bagged vs bulk mulch — which is cheaper?
Bulk is 50–70% cheaper per cubic foot. Break-even is usually around 5–7 cubic yards.
How long does mulch last?
Bark mulch: 1–3 years depending on type. Rubber mulch: 10+ years. Refresh annually for appearance.
How heavy is a cubic foot of mulch?
About 10–20 pounds per cubic foot dry; 25–40 lb wet.
Can I use too much mulch?
Yes. More than 4 inches can block water and air; piling against trunks ('mulch volcanoes') causes rot.
How do I calculate mulch for a curved bed?
Estimate the average length and width, multiply for an approximate area, then multiply by depth.