Mulch Calculator

Enter bed dimensions and desired depth — get cubic yards for bulk orders and bag counts for the garden center.

ft
ft
Keep mulch 2–3" deep; never pile against trunks.
beds

Your estimate

Cubic yards (exact)
Order (bulk)
2 cu ft bags
3 cu ft bags

Formula: (L × W × depth in feet × beds) ÷ 27 = cubic yards. One yard = 13.5 two-cu-ft bags. Bulk rounded up to the nearest half yard.

How to measure your beds

Walk each bed with a tape measure and record length and width in feet. Beds are rarely perfect rectangles — for curved or kidney-shaped beds, measure the longest length and the widest width, then multiply by 0.8 to approximate the true area. For a circular bed, use 3.14 × radius × radius.

Add up all your beds before ordering. The most common mistake in mulching is ordering per bed and paying three delivery fees — one combined bulk order is almost always cheaper. Depth is the number people guess at: 3 inches is the standard for a fresh bed, 2 inches for an annual top-up.

Bulk vs. bags

Bulk mulch from a landscape supplier typically costs $25–$55 per cubic yard plus a $40–$80 delivery fee, and it beats bagged mulch on price for anything over 2–3 yards. A cubic yard covers about 100 square feet at 3 inches deep — a useful rule of thumb when you're standing in the yard guessing.

Bags win for small jobs (under a yard), for beds you can't reach with a truck or wheelbarrow, and when you want a specific dyed or specialty product. Bagged mulch is also cleaner to transport in a car. The break-even is usually around 1.5–2 yards: below that, delivery fees eat the bulk savings.

Material tips

  • Depth discipline: 2–3 inches for most beds, 4 inches maximum. Deeper mulch sheds water, starves roots of oxygen, and invites voles.
  • Keep it off trunks. The "mulch volcano" around trees causes bark rot and girdling roots. Pull mulch 3–6 inches back from trunks and stems.
  • Shredded hardwood knits together and stays put on slopes; bark nuggets look tidy but float away in heavy rain.
  • Dyed mulches hold color about a year. Natural mulches fade faster but improve soil as they break down.
  • Weed barrier first? Landscape fabric under mulch helps in rock beds but is usually counterproductive under organic mulch — it blocks the decomposition that feeds your soil.
  • Refresh annually. Organic mulch decomposes roughly an inch per year. A spring top-up of 1–2 inches keeps beds at full depth.

What affects mulch cost

Bulk hardwood mulch runs $25–$55/yard; premium dyed, cedar, or pine bark products run $45–$75/yard. Delivery is typically $40–$80 within the supplier's radius. Bagged mulch at big-box stores runs $3–$6 per 2-cu-ft bag — $80–$160 per equivalent yard — so the convenience premium is real.

Professional mulching (labor + material) usually runs $70–$120 per cubic yard installed, including bed edging and cleanup. If your beds need redefining or weed removal first, expect that quoted separately.

Common mulching mistakes to avoid

  • Volcano mulching trees. Piling mulch against the trunk rots bark and invites disease — pull it back 3–4" from trunks and stems, keeping the root flare visible.
  • Going too deep. More than 4" of mulch suffocates roots and sheds water instead of absorbing it. Two to three inches, refreshed yearly, beats one deep dump.
  • Fresh chips against the house. Fresh wood mulch near siding can harbor termites and carpenter ants — keep a 6" mulch-free zone at the foundation, or use stone there.

Mulch FAQs

How do I calculate how much mulch I need?

Multiply length × width × depth (all in feet), divide by 27 for cubic yards. A 10×10 bed at 3 inches needs about 0.93 yards — order 1 yard.

How deep should mulch be?

2–3 inches for most beds, up to 4 inches for weed suppression. Never pile mulch against tree trunks or plant stems.

How many bags are in a cubic yard?

Fourteen 2-cu-ft bags, or nine 3-cu-ft bags, make one cubic yard.

Is bulk mulch cheaper than bags?

Usually 30–50% cheaper per yard above 2–3 yards, after delivery fees. Bags win for small beds and hard-to-reach areas.

When is the best time to mulch?

Spring, after the soil warms but before summer heat — typically April–May in most regions. A light fall top-up also works.

Big beds? Get it done for you.

Get free quotes from local landscapers for mulching, edging, and bed cleanup.

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