Understanding Mulch Calculations
Mulch is sold by the cubic yard for bulk delivery or in 2-cubic-foot bags at garden centers. Knowing how much you need helps you choose between bulk delivery (more economical for large areas) and bagged mulch (more convenient for small projects).
Recommended Mulch Depths
| Application | Depth | Notes |
|---|---|---|
| Annual Refresh | 1-2 inches | Over existing mulch |
| New Garden Beds | 2-3 inches | Standard recommendation |
| Tree Rings | 2-4 inches | Keep away from trunk |
| Weed Suppression | 3-4 inches | With landscape fabric |
| Pathways | 4-6 inches | More for foot traffic |
Mulch Types Comparison
| Type | Lifespan | Benefits |
|---|---|---|
| Shredded Hardwood | 1-2 years | Affordable, decomposes to enrich soil |
| Cedar Mulch | 2-3 years | Natural insect repellent, aromatic |
| Pine Bark | 2-3 years | Attractive, good for acid-loving plants |
| Colored/Dyed | 1-2 years | Consistent color, fades over time |
| Rubber Mulch | 10+ years | Long-lasting, great for playgrounds |
| Pine Straw | 1 year | Lightweight, easy to spread |
Bulk vs Bagged Mulch
One cubic yard of mulch equals about 13.5 bags (2 cubic feet each). For areas larger than 100 square feet at 3" depth, bulk delivery is typically more economical. Most landscape suppliers offer delivery for orders of 2-3 cubic yards or more.
Mulch Application Tips
- Keep mulch 2-3 inches away from plant stems and tree trunks
- Avoid the "mulch volcano" around trees - it causes rot and disease
- Apply mulch in spring after soil warms up
- Refresh annually rather than adding thick new layers
- Water the area before and after applying mulch
- Consider landscape fabric under mulch for weed control
- Fluff existing mulch with a rake before adding new material
Coverage Per Cubic Yard
One cubic yard of mulch covers approximately:
- 162 sq ft at 2" depth
- 108 sq ft at 3" depth
- 81 sq ft at 4" depth
- 54 sq ft at 6" depth