Free Landscape Calculator

Mulch Calculator

Calculate exactly how many cubic yards or bags of mulch you need for garden beds, trees and landscaping. Get instant results in cubic yards, bags and estimated cost.

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Mulch Calculator
Cubic yards, bags and cost
Dimensions
ft
ft
in
Quick Presets
📐 Your Results
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Cubic Yards
Bulk order
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2cu-ft Bags
If bagged
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Cubic Feet
Volume
Estimated Cost
Avg. $25–$45/cubic yard
$—
💡 Always order 10–15% extra for waste and settling.

📊 Understanding Your Results

Cubic Yards — Standard unit for bulk mulch delivery. One cubic yard covers approximately 108 sq ft at 3 inches deep.

2 cu-ft Bags — Standard bag size at most hardware stores. For large projects, bulk is 40–60% cheaper.

Cost Estimate — Based on average US bulk mulch prices of $25–$45 per cubic yard.

How the Mulch Calculator Works

Our mulch calculator uses a simple volumetric formula to estimate how much mulch you need. For most garden beds, 2–3 inches of mulch provides optimal weed suppression and moisture retention without smothering plant roots.

The Mulch Formula

Step 1: Volume (cubic feet) = Length × Width × Depth (all in feet)
Step 2: Cubic Yards = Cubic Feet ÷ 27
Step 3: Bags (2 cu ft) = Cubic Feet ÷ 2
Step 4: Add 10% extra for settling and uneven coverage

Example: A 15×8 ft garden bed at 3 inches = 120 × (3÷12) = 30 cu ft = 1.11 cubic yards = 15 bags.

Step-by-Step: How to Calculate Mulch

1
Measure your garden bed

Measure length and width in feet. For irregular shapes, break into rectangles and add totals.

2
Choose the right mulch depth

2 inches for light moisture retention, 3 inches for most garden beds, 4 inches for strong weed suppression.

3
Decide: bulk or bagged?

Under 2 cubic yards — bags may be more practical. Over 2 cubic yards — bulk delivery is significantly cheaper.

4
Apply mulch correctly

Keep 2–3 inches away from plant stems and 6 inches away from tree trunks to prevent rot and pest issues.

Recommended Mulch Depths by Application

ApplicationDepthBest Mulch Type
Annual flower beds2–3 inchesShredded hardwood
Around trees3–4 inchesPine bark nuggets
Vegetable gardens2–3 inchesStraw or shredded leaves
Weed suppression4–6 inchesAny dense mulch
Walkways and paths4–6 inchesWood chips or bark

Frequently Asked Questions

Common questions about calculating mulch for garden beds and landscaping.

How many cubic yards of mulch for 100 square feet?
For 100 sq ft at 3 inches deep: 100 × (3÷12) = 25 cubic feet ÷ 27 = 0.93 cubic yards — approximately 13 bags of 2 cu ft mulch.
How many bags of mulch equal a cubic yard?
One cubic yard = 27 cubic feet. A standard 2 cu ft bag requires 13.5 bags per cubic yard — always round up to 14. Bulk mulch is typically 40–60% cheaper than bagged.
What is the best mulch for garden beds?
Shredded hardwood is most popular — decomposes slowly and improves soil. Cedar mulch naturally repels insects. Pine bark nuggets work well around acid-loving plants. Straw is best for vegetable gardens.
Should I remove old mulch before adding new?
Generally no. If existing layer is under 2 inches, simply top it up. Remove or loosen if over 4 inches deep. Always maintain a 6-inch gap from tree trunks.
How much does a cubic yard of mulch cost?
Bulk mulch costs $20–$65 per cubic yard. Shredded hardwood: $20–$35/yard. Cedar mulch: $35–$55/yard. Delivery adds $50–$100. Bagged mulch costs roughly double bulk price.

💡 Pro Tips

Apply mulch in spring after the ground warms to suppress weeds all season.

Keep mulch 2–3 inches away from plant stems to prevent rot.

Refresh mulch every 1–2 years as it breaks down into the soil.