Mulch Calculator
Calculate exactly how much mulch you need for any garden bed. Get accurate quantities in cubic yards or bags, compare costs for different purchase options, and choose the right mulch type for your landscaping project.
Calculate Your Mulch Needs
Find out how much mulch to buy for your garden beds
Garden Bed Dimensions (feet)
2-3 inches for most beds, 4 inches for weed suppression
Economical, decomposes to enrich soil, needs annual replacement
Pricing ($)
Mulch Needed
10 cu ft
40 sq ft at 3" depth with Wood Chips
Volume
10 cu ft
0.37 cubic yards
2 cu ft Bags
5
$20.00
3 cu ft Bags
4
$20.00
Est. Weight
180 lbs
Wood Chips
Cost Comparison
Mulch Type Comparison
Maintenance Schedule
Wood Chips: Replace annually
Annual cost estimate: $12.96
Don't Forget
- Landscape fabric
- Garden edging
- Wheelbarrow
- Rake
- Work gloves
- Shovel
- Measuring tape
- Garden hose
How to Use This Calculator
Enter your garden bed dimensions in feet - length and width. For irregular shapes, break them into rectangles and add the totals, or measure the longest and widest points for an estimate.
Select your desired mulch depth. Most landscaping professionals recommend 2-3 inches for optimal weed suppression and moisture retention. Use 4 inches only for pathways or areas needing maximum coverage.
Choose your mulch type to see accurate weight estimates and replacement schedules. Different materials have very different densities - stone mulch weighs 5x more than wood chips per cubic foot.
Enter your local pricing for bulk and bagged mulch. The calculator will compare all options and highlight the best value for your project size.
Understanding Your Results
Cubic yards is the standard measurement for bulk mulch orders. One cubic yard equals 27 cubic feet and covers about 100 square feet at 3 inches deep. Most landscape suppliers deliver in cubic yard increments.
Bag quantities are shown for both 2 cubic foot and 3 cubic foot bags - the two most common retail sizes. The calculator rounds up since you cannot buy partial bags.
The cost comparison shows total price for each purchase option. Bulk is usually cheapest for large areas, but bags may be better for small projects or when you cannot receive a delivery.
Weight estimates help you plan transportation. A pickup truck typically holds 2-3 cubic yards of wood mulch safely, but only about 1 cubic yard of stone due to weight limits.
Frequently Asked Questions
How do I calculate how much mulch I need?
Multiply your garden bed's length by width to get square footage, then multiply by your desired depth (in feet). For example, a 10x4 foot bed at 3 inches deep needs: 10 x 4 x 0.25 = 10 cubic feet. Divide by 27 to get cubic yards (0.37 cu yds). Always round up when buying.
How many bags of mulch do I need for my garden?
First calculate cubic feet needed (length x width x depth in feet). Then divide by the bag size. For a 10x4 foot bed at 3" depth (10 cu ft): you need 5 bags of 2 cu ft mulch, or 4 bags of 3 cu ft mulch. Our calculator shows both options with cost comparison.
What is the ideal mulch depth for garden beds?
Most garden beds do best with 2-3 inches of mulch. Use 2 inches around perennials and in flower beds, 3 inches for shrub beds and general landscaping, and up to 4 inches for maximum weed suppression in pathways or low-maintenance areas. More is not better - too much mulch can suffocate plant roots.
Should I buy mulch in bags or bulk?
Bulk mulch (by cubic yard) is usually cheaper for larger projects - typically 50-60% less per cubic foot than bags. However, bags are more convenient for small areas, easier to transport, and better if you cannot receive a bulk delivery. Our calculator compares both options to find your best value.
What type of mulch is best for garden beds?
It depends on your needs: Wood chips are economical and enrich soil as they decompose (replace annually). Bark mulch lasts longer and looks attractive (18 months). Rubber mulch is permanent and great for playgrounds. Stone/gravel is permanent but does not add nutrients. Straw is best for vegetable gardens.
How much does a cubic yard of mulch weigh?
Weight varies by mulch type: Wood chips weigh about 400-500 lbs per cubic yard. Bark mulch is similar at 500-600 lbs. Rubber mulch is heavier at about 1,000 lbs. Stone and gravel are heaviest at 2,400-2,700 lbs per cubic yard. Consider weight when planning transport.
How often should I replace mulch?
Replacement frequency depends on mulch type: Straw needs replacing every 6 months. Wood chips last about 1 year. Bark mulch lasts 18 months. Rubber mulch lasts 10+ years. Decorative stone is permanent. Organic mulches break down and add nutrients to soil, which is a benefit of replacement.
Can I put new mulch over old mulch?
Yes, but first rake the old mulch to break up any matted layers and check total depth. Remove excess if adding new mulch would exceed 3-4 inches total. Old decomposed mulch adds nutrients to soil. If old mulch has fungus or disease, remove it completely before adding new mulch.
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