Mulch Calculator
Calculate exactly how many bags or cubic yards of mulch you need for your flower beds and landscaping.
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Mulch Bed Measurement
Measure the approximate Length and Width of your garden beds. For excellent weed suppression and moisture retention, aim for a mulch depth of 2 to 3 inches.
How to Use the Mulch Calculator
Whether you are buying bulk mulch delivered to your driveway or throwing bags in the back of your car, our mulch calculator tells you exactly what you need.
- Measure the garden beds: Find the length and width of the areas you want to mulch. If you have a circular bed, estimate it as a square to be safe.
- Set your depth: 3 inches is the industry standard for new mulch beds. If you are just refreshing an existing bed, 1 to 2 inches is sufficient.
- Read the bags: The calculator outputs results for both 2 cubic foot and 3 cubic foot bags—be sure to check the size printed on the bag at the store before loading your cart!
Mulch Calculator Formula
Mulch is sold by volume (cubic yards or cubic feet), making the math very straightforward.
Step 1: Calculate Square Footage
Area = Length (ft) × Width (ft)
Step 2: Calculate Cubic Feet
Volume (ft³) = Area × (Depth in inches ÷ 12)
Step 3: Convert to Yards
Cubic Yards = Cubic Feet ÷ 27
Step 4: Calculate Bags
2 cu ft Bags = Cubic Feet ÷ 2
3 cu ft Bags = Cubic Feet ÷ 3
Mulch Example
You have a flower bed along the front of your house that is 30 feet long and 4 feet deep. You want 3 inches of new mulch.
- Area: 30 × 4 = 120 square feet.
- Volume: 120 × (3/12) = 30 cubic feet.
- Convert to yards: 30 ÷ 27 = 1.11 cubic yards.
- Convert to bags: 30 ÷ 2 = 15 bags (2 cu ft size).
Conclusion: Since delivery fees for just 1 yard are expensive, it makes sense to go to the hardware store and buy fifteen 2-cubic-foot bags.
Tips for Mulching
- Pull weeds first: Never put mulch directly over living weeds. Pull them out by the roots first.
- Edge your beds: Use a spade to cut a crisp "V" shaped trench around the border of your beds. This gives the mulch a place to sit without washing out into your lawn during heavy rain.
- Keep it away from siding: Leave a 1-2 inch gap between the mulch and your home's foundation or siding to prevent termites and rot.
Frequently Asked Questions
How many bags of mulch are in a cubic yard?
There are 13.5 bags of 2-cubic-foot mulch in one cubic yard. If you are buying 3-cubic-foot bags, there are exactly 9 bags in a cubic yard.
How thick should I spread mulch?
The ideal depth for mulch is 2 to 3 inches. This is thick enough to suppress weeds and retain moisture, but thin enough to allow water and oxygen to reach the soil. Never pile mulch against the trunk of a tree (avoid 'mulch volcanoes').
Is it cheaper to buy bagged mulch or bulk mulch?
Bulk mulch delivered by the yard is almost always cheaper than buying individual bags if you need more than 3 cubic yards. However, if you only need 1 or 2 yards, buying bags and transporting them yourself in a car or SUV is more cost-effective since you avoid delivery fees.
How much area does one bag of mulch cover?
One 2-cubic-foot bag of mulch will cover exactly 12 square feet at a depth of 2 inches. One 3-cubic-foot bag will cover exactly 18 square feet at a depth of 2 inches.