The formula
Cubic feet = length in feet × width in feet × depth in inches ÷ 12. Cubic yards = cubic feet ÷ 27. Bags = cubic feet ÷ the bag size, rounded up. For a circle, the area is 3.14 × the radius × the radius.
Buy enough, without buying a mountain
How much mulch do I actually need?
Tell us the size of the area and how deep you want the mulch. We’ll tell you how many bags or cubic yards to buy—even if you are adding to mulch you already have.
What area are you covering?
1160 square feet of ground will be covered.
How deep should the mulch be?
2How will you buy it?
3160 square feet · 3 inches deep
1.63cubic yards
Or buy 22 bags at 2 cubic feet each.
- Total to buy
- 44 cubic feet
- Before extra
- 40 cubic feet
- Extra included
- 10%
Measure the whole bed instead of subtracting every plant—the soil around them still needs mulch. Keep a few inches clear around stems and trunks.
Bulk delivery is usually easier for several cubic yards. Bags are easier for small beds, steps, or places a wheelbarrow cannot reach.
The math, done for you
Mulch conversions and coverage
How many bags are in a cubic yard?
| Cubic yards | 1.5 cu ft bags | 2 cu ft bags | 3 cu ft bags |
|---|---|---|---|
| 1 | 18 | 14 (13.5) | 9 |
| 2 | 36 | 27 | 18 |
| 3 | 54 | 41 (40.5) | 27 |
| 4 | 72 | 54 | 36 |
| 5 | 90 | 68 (67.5) | 45 |
| 10 | 180 | 135 | 90 |
Exact counts in brackets; buy the rounded-up number.
How far does it go?
| Depth | 1 cubic yard | One 2 cu ft bag | One 3 cu ft bag |
|---|---|---|---|
| 1 inch | 324 sq ft | 24 sq ft | 36 sq ft |
| 2 inches | 162 sq ft | 12 sq ft | 18 sq ft |
| 3 inches | 108 sq ft | 8 sq ft | 12 sq ft |
| 4 inches | 81 sq ft | 6 sq ft | 9 sq ft |
Worked examples
- A 10 by 20 foot bed at 3 inches: 200 square feet × 3 ÷ 12 = 50 cubic feet, about 1.85 cubic yards, or 25 bags of 2 cubic feet.
- A 10 by 10 foot bed at 3 inches: 25 cubic feet, about 0.93 cubic yards, or 13 bags of 2 cubic feet.
- A ring 8 feet across around a tree at 3 inches: about 50 square feet (3.14 × 4 × 4), so about 12.6 cubic feet, or 7 bags of 2 cubic feet.
- Topping up 300 square feet by 1 inch: 25 cubic feet, about 0.93 cubic yards, or 13 bags of 2 cubic feet.
How deep for each kind of mulch
- Shredded bark and hardwood: 2 to 3 inches around shrubs, perennials and trees.
- Coarse wood chips: 3 to 4 inches, best under trees and on paths.
- Pine straw: about 3 inches when freshly spread, since it settles. It is sold by the bale rather than by the cubic foot.
- Fine shredded mulch or compost: 1 to 2 inches, because fine material packs down and can shed water.
- Whatever the type, keep it a few inches back from stems and trunks.
Bags or bulk?
A cubic yard of bulk mulch is the same volume as 13.5 bags of 2 cubic feet. Multiply your bag price by 13.5 and compare it with the bulk price per yard plus delivery. Bulk usually wins on bigger jobs; bags win when you need less than a yard, when there is nowhere to tip a load, or when the mulch has to go through a gate or up steps.
How to use the answer
A little mulch goes a long way.
Mulch helps soil stay moist and protects plant roots from heat and cold when it is spread evenly.
- Add only enough to replace what has broken down; do not pile on three new inches every year.
- Keep mulch away from the base of stems and trunks instead of piling it into a mound.
- For an unusual shape, measure a few smaller sections and add the amounts together.
Where the information comes from
- University of Florida IFAS Extension — Mulch — how deep to spread mulch and how to protect plants
Questions gardeners ask
How many bags of mulch are in a cubic yard?
A cubic yard is 27 cubic feet, so it equals 13.5 bags of 2 cubic feet, 9 bags of 3 cubic feet, or 18 bags of 1.5 cubic feet. Round partial bags up when you buy.
3 cubic yards of mulch is how many bags?
Three cubic yards is 81 cubic feet: 41 bags of 2 cubic feet (40.5 rounded up), 27 bags of 3 cubic feet, or 54 bags of 1.5 cubic feet.
How many square feet does one cubic yard of mulch cover?
One cubic yard covers about 324 square feet at 1 inch deep, 162 square feet at 2 inches, 108 square feet at 3 inches, or 81 square feet at 4 inches.
How much area does a 2 cubic foot bag of mulch cover?
About 24 square feet at 1 inch deep, 12 square feet at 2 inches, or 8 square feet at 3 inches. A 3 cubic foot bag covers half as much again: 36, 18 or 12 square feet.
How much mulch do I need for a 10 by 10 area?
A 10 by 10 foot bed is 100 square feet. At 3 inches deep it needs 25 cubic feet, about 0.93 cubic yards or 13 bags of 2 cubic feet. At 2 inches it needs about 17 cubic feet, or 9 bags.
Is it cheaper to buy mulch in bulk or in bags?
Compare like with like: multiply the price of a 2 cubic foot bag by 13.5 to get the bagged price of a cubic yard, then set it against the bulk price per yard plus delivery. Bulk usually wins on bigger jobs; bags win for small beds, for less than a yard, or where a load cannot be tipped near the beds.
Should I subtract the space taken up by plants?
Usually no. Mulch still covers the soil beneath and between plants. Measure the whole bed, then keep a few inches clear around stems and trunks.
How much extra mulch should I buy?
Adding 10% is a useful cushion for uneven ground, settling, and measurements that are not exact. You may need less for a simple bed and more for an irregular area.
How deep should mulch be?
Two to three inches works well around most established shrubs, trees, and flower beds. Coarse wood chips can go to 3 or 4 inches, while fine shredded mulch and compost are best at 1 to 2 inches because they pack down.