Mulch Calculator
Enter length, width, and depth — get bags, cubic yards, and cost in seconds.
Add 10% for waste and settling (recommended)
Mulch settles ~50% over one year. To restore a 3" depth, you'll need approximately 9 bags (2 cu ft) at 1.5" top-up depth for this same area. Applies to organic mulch (wood, bark, cedar). Rubber mulch does not decompose and rarely needs topping up.
Mulch typically weighs 400–1,200 lbs per cubic yard depending on type and moisture content. For your volume (1.22 yd³), expect roughly 489–1,467 lbs. Weights are approximate and vary significantly — check with your supplier before transport.
Compare mulch types.
The five most common landscape mulches in the US — what each costs, how long it lasts, what it's best for.
| Mulch type | Lifespan | Cost / yd³ | Best for | Notes |
|---|---|---|---|---|
| Hardwood bark | 1–2 years | $30–45 | Garden beds, paths | Most common; breaks down and enriches soil |
| Cedar | 3–5 years | $40–55 | Beds, borders | Natural insect resistance; pleasant aroma |
| Cypress | 2–3 years | $35–50 | Slopes, beds | Holds well on slopes; resists washing away |
| Pine bark / straw | 1–2 years | $25–40 | Acid-loving plants | Lowers soil pH slightly; lightweight |
| Rubber | 10+ years | $80–120 | Playgrounds, paths | Does not decompose; no soil benefit |
Quick reference: bags of mulch needed.
Based on standard 2 cu ft bags with 10% waste factor included.
| Area (sq ft) | 2" deep | 3" deep | 4" deep |
|---|---|---|---|
| 50 | 5 bags | 7 bags | 10 bags |
| 100 | 10 bags | 14 bags | 19 bags |
| 150 | 14 bags | 21 bags | 28 bags |
| 200 | 19 bags | 28 bags | 37 bags |
| 250 | 23 bags | 35 bags | 46 bags |
| 300 | 28 bags | 42 bags | 55 bags |
| 400 | 37 bags | 55 bags | 74 bags |
| 500 | 46 bags | 69 bags | 92 bags |
| 600 | 55 bags | 83 bags | 110 bags |
| 800 | 74 bags | 110 bags | 147 bags |
| 1,000 | 92 bags | 138 bags | 184 bags |
| 1,500 | 138 bags | 207 bags | 275 bags |
What is mulch?
Mulch is a layer of material — usually shredded bark, wood chips, or pine straw — spread over bare soil around plants and trees. It holds moisture in the ground, blocks weeds from getting sunlight, and keeps soil temperature steady through hot and cold swings. As organic mulch breaks down, it adds nutrients back into the soil.
Most homeowners buy mulch in 2 cu ft bags from Home Depot or Lowe's. For larger projects, bulk mulch from a landscape supplier is cheaper per yard, but delivery usually costs $50–150 per truckload, and that fee eats the savings on small orders. At typical regular prices, bulk only pulls ahead past about 5–6 cubic yards. Our bulk vs. bagged mulch comparison breaks down exactly when each option makes sense.
Recommended mulch depths.
Getting the depth right matters more than most people think. Too thin and weeds push through. Too thick and you suffocate the roots you're trying to protect.
For flower beds and shrubs, aim for 2–3 inches. Pathways need 3–4 inches because foot traffic compresses the material faster. Around trees, use the same 2–3 inch depth but spread it wide — at least to the drip line — and keep a 3–6 inch gap around the trunk. Never pile mulch against the bark (that's called "volcano mulching," and it traps moisture that causes rot and disease).
For containers and pots, 1–2 inches is plenty.
The hard rule: never exceed 4 inches total. More than that blocks water and air from reaching the roots, which does more harm than good. See our guide on how much a yard of mulch covers for detailed coverage charts by depth. Source: Penn State Extension, Clemson Cooperative Extension.
How to measure your area.
Grab a tape measure and measure in feet. For a rectangular bed, you just need length and width — plug them into the calculator above.
Irregular shapes? Break the area into simpler pieces. An L-shaped bed becomes two rectangles. A curved border can be approximated as a series of rectangles or a trapezoid. The calculator supports rectangles, circles, L-shapes, triangles, rings (for around trees), and trapezoids — use whichever fits closest.
For circular areas like tree rings, measure the diameter (straight across the widest point) and use the circle shape option.
One tip: always round your measurements up. Having a bag or two left over is no big deal. Running out mid-project means a second trip to the store — covered in dirt, on a Saturday afternoon, when the checkout line wraps around the garden center.
How we calculate.
The calculator uses the standard formula recommended by university extension services:
That gives you total volume in cubic yards. To get the number of bags, divide total cubic feet by the bag size (1.5, 2, or 3 cu ft) and round up — stores don't sell partial bags. For a step-by-step walkthrough, see how to calculate how much mulch you need.
The 10% waste toggle (on by default) adds extra to account for spillage during spreading, settling in the first few weeks, and bags that aren't filled to the brim. Landscapers routinely add this buffer, and we recommend you do too.
When to apply mulch.
Spring is the most popular time, but don't rush it. Wait until the soil has warmed up — mid-April at the earliest, often into May depending on your region. Mulching too early traps cold moisture in the ground and slows root growth right when plants need to take off.
Fall is your second window. A fresh layer before the first frost insulates roots through winter and gives you a head start on spring.
Plan to top up every year. Organic mulch (bark, wood chips, cedar) settles about 50% over 12 months as rain compacts it and microbes break it down. If you started at 3 inches, expect about 1.5 inches by next spring — just add another layer to bring it back up. Source: UF/IFAS Extension.
Frequently asked questions.
How many bags of mulch is a cubic yard?
One cubic yard = 27 cubic feet. In standard 2 cu ft bags, that's 14 bags. For 1.5 cu ft bags, you'll need 18. For the larger 3 cu ft bags, 9 will do it. Always round up since you can't buy half a bag. Our guide on how many bags of mulch are in a cubic yard has the full table by bag size.
How deep should mulch be?
2–3 inches for flower beds and shrubs. 3–4 inches for pathways. Never more than 4 inches total — thicker layers block water and air from reaching roots. Around trees, keep the same depth but leave a 3–6 inch gap between the mulch and the trunk to prevent rot.
Should I buy mulch in bags or bulk?
For small to mid-size projects (under about 70 bags, roughly 5 cubic yards), bagged mulch is usually cheaper and easier — just load them in your car. Past about 5–6 cubic yards, bulk delivery wins ($25–55/yd³ for most wood mulches, plus $50–150 delivery). Watch for spring sales at Home Depot and Lowe's — bags sometimes drop to $2 each, which can beat bulk pricing on smaller jobs.
How much area does a yard of mulch cover?
At 2 inches deep: 162 sq ft. At 3 inches deep: 108 sq ft. At 4 inches deep: 81 sq ft. The formula is 27 ÷ depth in feet. For example, 3 inches = 0.25 feet, so 27 ÷ 0.25 = 108 sq ft.
Can I put new mulch over old mulch?
Yes, as long as the old layer has broken down to about 1 inch or less. Just add enough new mulch to bring the total depth to 2–3 inches — don't exceed 4 inches. If the old mulch is matted, compacted, or has a sour smell, rake it up to loosen it before adding the new layer. This lets air and water flow through properly.
How long does mulch last?
It depends on the type. Hardwood bark: 1–2 years. Cypress: 2–3 years. Cedar: 3–5 years. Rubber mulch: 10+ years (but adds nothing to the soil). Most organic mulch settles about 50% per year, so plan to top it up each spring.
How much bulk mulch fits in a pickup truck?
A full-size pickup typically holds about 2.5 cubic yards when filled level to the top; a compact or midsize truck about 1.5 cubic yards. Check your truck's payload capacity first — there's a sticker on the driver's side door jamb. Wet mulch is significantly heavier than dry, and overloading can damage your suspension or tires.
Methodology & sources
Every recommendation, formula, and number on this page is traceable to university extension publications or verified US retail pricing. Calculations use Python's Decimal type to avoid floating-point drift.
Depth and trunk clearance guidelines
- Penn State Extension — Mulching Landscape Trees — link
- Clemson Cooperative Extension — Mulch Factsheet — link
- Rutgers NJAES — FS099: Problems With Over-Mulching — link
Calculation formulas
- Iowa State Extension — How to Determine Amount of Mulch Needed for a Garden Bed — link
- Mississippi State Extension — P2301: Mulches for the Landscape — link
- UNH Cooperative Extension — Mulching Trees and Shrubs — link
Decomposition and settling rates
- Oregon State Extension — EC-1629: Mulching Woody Ornamentals With Organic Materials — link
- UF/IFAS — FR052: Landscape Mulches: How Quickly Do They Settle? — link
Application timing
- Iowa State Extension — Using Mulch in the Garden — link
Pricing. Retail bag prices verified against HomeDepot.com and Lowes.com US storefronts; bulk prices taken from published price lists of landscape supply yards in several US regions. Reviewed once a year, before the spring season. The calculator's price fields are editable — replace with your local quote for an exact estimate.
Last methodology review: June 2026.
Independence: Sources are cited for reference only. The universities, agencies and retailers named on this page do not sponsor or endorse MaterialCalcs, and we are not affiliated with them. Retail prices were checked by hand and vary by store and region.
Read next.
Bulk vs. bagged mulch: when does each make sense?
When you save by bulk, when bagged wins on convenience. The math, including delivery fees.
How long does mulch last?
Undyed hardwood: 2–3 seasons. Dyed black: 12 months of color. Pine bark nuggets outlast them all.
Mulch vs. rock: which is better for your yard?
Rock is cheaper over 10 years. Mulch is better for plants. The honest trade-off.