Mulch & Gravel Calculator
Bulk materials by area + depth. Works for mulch, gravel, river rock, topsoil — anything you spread to a uniform depth.
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Cubic yards (for bulk delivery)
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Cubic feet
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Cubic meters
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2 cuft bags
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Bagged vs bulk
The crossover is roughly 1–2 cubic yards (around 15–30 bags):
- Less than 1 cu yd: bags from the garden center. Easier to handle, no delivery fee, no shovel marathon.
- 1–3 cu yd: either. Bulk costs ~30–50% less per cuft but adds a delivery fee and dumping logistics.
- 3+ cu yd: bulk delivery wins on cost and effort. Have a tarp ready.
Depth guidelines
- Mulch (decorative beds): 2" if topping up existing mulch, 3" if establishing new. More than 4" suffocates roots.
- Mulch (around trees): 3" max, donut-shape (not piled against the trunk — that's "volcano mulching" and damages bark).
- Gravel (paths): 2–3" over compacted base.
- Gravel (driveways): 4–6", in layers, compacted between.
- Topsoil (new lawn): 4–6". Less if amending existing soil.
Bag weights
"2 cuft" is the standard bag size, but weight varies by material — mulch is ~20 lb/cuft (so a 2cuft bag = ~40 lb), gravel is 90–100 lb/cuft (a 2cuft bag = ~180 lb, which is why bags top out at 50 lb for gravel). Don't lift past your back limits.