How many bags of mulch do I need for 100 square feet?
Check it with your own numbers
Open the Mulch Calculator with these values
| Length | 10 ft |
| Width | 10 ft |
| Depth | 3 in |
| Mulch needed | 0.93 yd³ |
| 2 ft³ bags | 13 |
| 3 ft³ bags | 9 |
How we got 13 bags
100 ft² × 0.25 ft (3 inches) = 25 cubic feet. Most bagged mulch is sold in 2 ft³ bags, so 25 ÷ 2 rounds up to 13. Some brands sell 3 ft³ bags; you need 9 of those. In bulk terms that is 0.93 yd³.
Depth makes the biggest difference
The same 100 ft² needs very different amounts depending on depth:
- 2 inches: a refresh layer over last year's mulch. About two-thirds of the bags above.
- 3 inches: the standard for a new bed. Blocks light well enough to slow weeds.
- 4 inches: only for bare, weedy ground or under play equipment with wood chips. Thicker than this and you start starving roots of air.
Bagged vs bulk at 100 square feet
At under a cubic yard, bags usually win. Bulk mulch is often cheaper per yard, but most landscape yards charge a delivery fee that wipes out the savings on small jobs. If you have a pickup, a single scoop from the yard is roughly 1 yd³ and covers this job with a little left over.
Spreading tips
- Pull mulch 2 to 3 inches back from tree trunks and plant stems. Mulch piled against bark invites rot and rodents.
- Edge the bed first with a flat spade. A clean 2-inch-deep edge keeps mulch in place.
- Water the bed before you spread. Mulch over dry soil can shed rain for weeks.
- Dump bags in small piles across the bed, then rake. Fewer trips with a heavy bag.
Which mulch?
Shredded hardwood knits together and stays put on slopes. Pine bark nuggets look clean but float in heavy rain. Dyed mulch holds color for about a season. Bag yields are the same for all of them, so the 13-bag count holds whichever you pick.
Related questions
For other sizes, use the full Mulch Calculator or browse all answers.