Mulch Calculator
Calculate cubic yards and bags of mulch needed for your landscape beds, tree rings, and garden areas. Compare bulk vs bagged pricing.
How to Use This Calculator
Getting the right amount of mulch saves money and multiple trips to the garden center. Here's how to calculate accurately:
- Measure your garden beds, tree rings, or landscaped areas. For irregular shapes, break them into rectangles and add the areas together.
- Choose your desired mulch depth. 2-3 inches is standard for beds, 3-4 inches for pathways.
- Select your mulch type to get accurate weight estimates for delivery planning.
- Enter local pricing to compare bulk vs bagged costs.
- Click 'Calculate' to see cubic yards, number of bags, and cost comparison.
Why This Matters
Mulch is one of the most important landscape materials - it conserves moisture, suppresses weeds, regulates soil temperature, and improves appearance. But too little mulch doesn't provide these benefits, and too much can harm plants by smothering roots and trapping excessive moisture.
- Calculate exactly how much mulch you need - no more guessing
- Compare bulk vs bagged costs to find the best value
- Know the weight for planning delivery or pickup
- Avoid over-mulching which can harm plants
- Plan your budget accurately before purchasing
Worked Examples
Small Flower Bed
A 6' × 10' flower bed at 3 inches of mulch depth.
Calculation: 60 sq ft × (3/12) ft = 15 cubic feet ÷ 27 = 0.56 cubic yards
Result: You need 8 bags (2 cu ft each) or about half a cubic yard bulk.
Large Landscape Area
500 square feet of beds around the house at 3 inches deep.
Calculation: 500 sq ft × 0.25 ft = 125 cubic feet ÷ 27 = 4.6 cubic yards
Result: Order 5 cubic yards bulk. This would require 63 bags - bulk is much more economical.
Tree Rings
5 tree rings, each approximately 6 feet diameter at 4 inches deep.
Calculation: 5 × (π × 3² sq ft) × (4/12 ft) = 47 cubic feet = 1.74 cubic yards
Result: Order 2 cubic yards bulk or 24 bags. Keep mulch 6 inches away from tree trunks.
Common Mistakes to Avoid
- Piling mulch against tree trunks ('volcano mulching') - this causes rot and pest problems. Keep mulch 6 inches away from trunks.
- Applying mulch too deep - more than 4 inches can prevent water from reaching roots and harbor pests.
- Not removing old, compacted mulch before adding new - turn or remove old mulch that's become water-repellent.
- Buying bags when bulk is cheaper - for 3+ cubic yards, bulk delivery often saves 30-50%.
- Forgetting to account for irregular shapes - break complex beds into rectangles for accurate measurement.