Mulch Calculator - Cubic Yards, Bags & Bed Cost
Mulch volume is bed area times depth. The calculator converts to bulk cubic yards, bag count, and cost so you can compare bulk delivery against bagged mulch.
Bag volume printed on the product bag, not bag weight.
Percent added for cuts, waste, settlement, or field loss.
Cost uses the rounded bag count.
Change any value and the results, formula, and diagram update immediately. Use the same unit system throughout one estimate.
Mulch Quick Reference
Mulch needed for common bed sizes at 2 and 3 inch depths. Bags shown are standard 2 cu ft retail bags. Use the calculator for your specific depth.
| Bed area | 2 in deep (yd³) | 3 in deep (yd³) | 3 in @ 2 cu ft bags |
|---|---|---|---|
| 50 sq ft | 0.31 | 0.46 | 7 bags |
| 100 sq ft | 0.62 | 0.93 | 13 bags |
| 200 sq ft | 1.23 | 1.85 | 25 bags |
| 500 sq ft | 3.08 | 4.62 | 63 bags |
| 1000 sq ft (whole-yard refresh) | 6.17 | 9.26 | 125 bags |
One cubic yard of mulch covers 100 sq ft at 3 in. The same yard equals roughly 13.5 of the 2 cu ft bags - bulk wins decisively above 1 yard.
How Much Depth Mulch Needs
- New beds: 3 inches (75 mm) of mulch on top of weed barrier or bare soil.
- Refreshing existing beds: 1-2 inches over last year's layer.
- Around trees and shrubs: 2-3 inches, but pulled back 3-6 inches from trunks (the "volcano" mistake - piling mulch against bark - rots the tree).
- Vegetable garden: 2-3 inches of straw, leaves, or organic mulch. Less for finer materials.
- Playgrounds (rubber or wood chip): 6-12 inches for impact attenuation per ASTM F1292.
- Pathways and walkways: 3-4 inches of bark or wood chip over weed barrier.
Mulch settles 25-30% after watering. Order accordingly - what looks like 4 inches on day 1 is 3 inches a month later.
Mulch Types
Hardwood (shredded)
The US default. Mixed deciduous wood, sometimes dyed brown or black. Breaks down in 1-2 years, feeding soil. Annual refresh.
Cedar / cypress
Longer-lasting (2-3 years), insect-repellent scent, lighter colour. Premium price. Good for high-visibility ornamental beds.
Pine bark
Nuggets (1-3 in chunks) or fine pine shreds. Slightly acidic - excellent under rhododendrons, azaleas, blueberries. Floats; not ideal on slopes.
Pine needles / pine straw
Sold in bales (about 25-35 sq ft each at 3 in). Natural look, lightweight, slows water evaporation. Common in southern US.
Dyed mulch (red, black)
Recycled wood with mineral dye. Holds colour 6-12 months then fades. Some products use recycled pallets (potential treated-wood concerns).
Rubber mulch
Recycled tire chips. Does not decompose. Excellent for playgrounds; debated for garden beds (heat, microplastics).
Compost / leaf mould
Fully decomposed organic matter. Best soil-builder but breaks down within months. Combine with topcoat of bark mulch.
Straw / hay
Vegetable gardens, freshly seeded lawns. Cheap, decomposes in one season. Watch for weed seeds in cheap hay.
Bag Sizes Around The World
| Region | Standard bag | Coverage at 3 in |
|---|---|---|
| United States | 2 cu ft (~28 L) | 8 sq ft per bag |
| United States (small) | 1 cu ft / 3 cu ft | 4 / 12 sq ft per bag |
| United Kingdom | 60 L bulk bag, 100 L jumbo | 8 / 14 sq ft per bag |
| Eurozone | 50 L, 70 L, 100 L bags | 7 / 10 / 14 sq ft per bag |
| Australia | 30 L, 50 L bags; 1 m³ bulk bags | 4 / 7 sq ft per bag |
| India | Less common bagged; sold by trolley loads (~1 m³) | covers ~120 sq ft at 3 in |
Cost Estimates Around The World
2026 retail prices for hardwood and bark mulch.
| Region | Bulk hardwood / bark | Bagged retail | Cedar premium | Pine straw bale |
|---|---|---|---|---|
| United States (USD) | $30-60 / yd³ delivered | $4-7 per 2 cu ft bag | $50-90 / yd³ | $5-9 per bale |
| Canada (CAD) | C$45-90 / yd³ | C$6-10 per 56 L bag | C$70-120 / yd³ | C$8-12 per bale |
| United Kingdom (GBP) | £40-80 / m³ delivered | £5-9 per 60 L bag | £60-110 / m³ (chipped bark) | n/a (limited market) |
| Eurozone (EUR) | €40-90 / m³ | €5-12 per 60 L bag | €70-130 / m³ | n/a |
| Australia (AUD) | A$70-140 / m³ | A$10-20 per 50 L bag | A$120-220 / m³ | A$15-25 per bale (lucerne) |
| India (INR) | ₹1,000-3,500 / m³ (rare - usually compost or paddy straw) | limited retail | n/a | ₹200-500 per bale |
| Mexico (MXN) | MX$500-1,200 / m³ | MX$80-180 per 50 L bag | MX$1,000-2,000 / m³ | MX$150-300 per bale |
| Philippines (PHP) | PHP 1,500-3,500 / m³ | PHP 150-300 per 25 L bag | PHP 2,500-5,000 / m³ | PHP 200-450 per bale |
Common Mistakes
- The "mulch volcano" - piling mulch against tree trunks. Rots bark, encourages pests, can kill the tree.
- Mulch too deep (5+ inches) - smothers shallow roots, holds moisture against crowns.
- Buying bags for jobs over 2 yards - bulk delivery is cheaper and faster.
- Forgetting that mulch settles 25-30% - order extra for refresh.
- Dyed mulch in vegetable gardens (some dyes contain unwanted chemicals).
- Rubber mulch in flower beds - does not feed soil, looks artificial up close.
- Pine needles on flat beds without containment - they blow around.
- Not refreshing mulch annually - faded, decomposed mulch becomes weed habitat.
Mulch Calculator FAQ
How many bags of mulch for a 200 sq ft bed?
At 3 in deep: 200 x 0.25 = 50 cu ft of mulch. With 2 cu ft bags, that is 25 bags. With 3 cu ft bags, 17 bags. Order an extra bag or two for refresh and uneven depth.
How deep should mulch be?
3 inches (75 mm) for new beds, 1-2 inches when refreshing. Pull back 3-6 inches from tree trunks - never pile mulch against bark. Playgrounds use 6-12 inches for impact safety.
How many cubic yards of mulch do I need?
For 1000 sq ft at 3 in deep: 1000 x 0.25 / 27 = 9.26 cu yd. Round to 10 yards for delivery (1-yard truck minimums are common, so order in whole yards).
How much does mulch cost?
US: $30-60 per yd³ bulk delivered, $4-7 per 2 cu ft bag retail. UK: £40-80 per m³. India: ₹1,000-3,500 per m³ (compost or paddy straw is more common). Premium cedar and dyed mulches cost 50-100% more.
What is the best mulch for my garden?
Hardwood shredded is the all-purpose default. Cedar for ornamental visibility and longer life. Pine bark for acid-loving plants. Straw for vegetable gardens. Avoid rubber mulch in beds with plants.
Should I put landscape fabric under mulch?
Fabric reduces weed growth temporarily but eventually mulch decomposes into the fabric, weed seeds blow on top, and the fabric becomes a maintenance problem. Many landscapers now skip fabric and rely on 3 in deep mulch alone.
How often should I replace mulch?
Annually for thin layers (1-2 in refresh). Every 2-3 years for full replacement. Hardwood and dyed mulches lose colour in 6-12 months; cedar holds colour 1-2 years.
Is dyed mulch safe for vegetables?
Iron-oxide dyes are inert and safe. The concern is the source wood - some recycled mulch comes from pallets that may have treated wood. For edibles, use undyed natural mulch from a reputable supplier.
Does mulch attract termites?
Some risk if mulch touches house siding or wood structures. Keep mulch 6 in away from foundations and 12 in below siding. Termites prefer wet wood directly against soil, not loose mulch.
Can I make my own mulch?
Yes - chipped branches, leaves, grass clippings (mixed, dry), shredded paper. Compost first if using grass clippings to avoid matting. Free or near-free; some communities offer free wood chips from tree-trimming contractors.
Related Construction Calculators
For topsoil and lawn soil, use the Topsoil Calculator. For decorative landscape stone, see the Stone Calculator. For lot area measurement, use the Land Area Calculator. More tools live on the Construction Calculators hub.
Sources
- University of Minnesota Extension - mulch guidance
- International Society of Arboriculture - tree mulching practices
- ASTM F1292 standard for impact-attenuating playground surfaces
- EPA green landscaping resources
- Royal Horticultural Society (UK) mulching guide
- NIST Handbook 44 unit conversion tables
This calculator is for planning and ordering conversations. Local code, project drawings, engineered design, and manufacturer instructions control the final work.