Mulch Calculator
Find out how much mulch your garden beds need — in cubic feet, cubic yards, and the exact number of 2 cu ft or 3 cu ft bags.
Results
Mulch settles after rain; adding a small amount extra is fine, but avoid piling it against tree trunks.
How to Use This Mulch Calculator
- Measure the length and width of each bed in feet.
- Pick the depth — 2–3 inches is the sweet spot for most beds.
- Add the results for separate beds together, or calculate them one at a time.
The calculator multiplies length × width × depth (converted to feet) to get cubic feet, then converts to cubic yards (27 cu ft = 1 cu yd) and bag counts.
How Deep Should Mulch Be?
| Situation | Recommended depth |
|---|---|
| Refreshing an established bed | 1–2 in |
| Most flower beds and borders | 2–3 in |
| Newly planted shrubs and trees | 3–4 in (never touching the trunk) |
Bagged vs. Bulk Mulch
Home centers sell mulch in 2 cu ft bags (often about 40 lbs when dry) and 3 cu ft bags. Bulk suppliers sell by the cubic yard, usually with a minimum delivery quantity.
- Small beds (under ~30 sq ft): bags are simplest.
- Large beds (100+ sq ft): price a bulk delivery — it is typically 30–50% cheaper per yard.
One caveat: bulk mulch is often sold "by the yard" before settling, so it can compress to noticeably less than a full yard once spread.
Frequently Asked Questions
How many bags of mulch are in a cubic yard?
One cubic yard equals 27 cubic feet, so it takes about 14 bags of 2 cu ft mulch or 9 bags of 3 cu ft mulch.
How much mulch do I need for a 10x10 bed 3 inches deep?
A 10×10 bed at 3 inches deep is 25 cubic feet, which is just under 1 cubic yard: about 13 bags of 2 cu ft or 9 bags of 3 cu ft.
How deep should mulch be?
2–3 inches is right for most flower beds and borders. 1 inch is enough for established beds, and more than 4 inches can smother plant roots.
Is bagged or bulk mulch cheaper?
Bulk mulch sold by the cubic yard is almost always cheaper per yard for large beds, but bagged mulch is easier for small areas and can be returned when unopened.