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Larch mulch chart
Put your larch mulch area, depth and waste in: 1300 square feet at 4 inches with 10% waste needs 1,430.00 square feet — 17.65 cubic yards exact, order 18 cubic yards.
★ CONSTRUCTION · REFERENCE TABLE #505 · LARCH MULCH
Larch Mulch Chart: 1300 Sq Ft, 4 Inches, Order 18 Yards
On the defaults — 1300 square feet at 4 inches deep with 10% waste — larch mulch needs 1,430.00 square feet, 17.65 cubic yards exact, order 18 cubic yards. This is the LARCH version — the same area-times-depth shape as the chestnut-mulch-chart page, the sycamore-mulch-chart page and the beech-mulch-chart page — with the larch figures and the 16-row lookup table worked in full.
What does 17.65 cubic yards of larch mulch mean?
It means 1,430.00 square feet of bed, once 10% waste is added to 1300 square feet, covered 4 inches deep. A cubic yard covers 324 square feet at 1 inch, so at 4 inches one yard covers only 81.0 square feet, and 1,430.00 ÷ 81.0 is 17.65 yards. The order rounds up to 18 because mulch is delivered by the whole yard: ordering 17 would leave more than half a yard short, and a bare patch at the far end of the last bed. The 0.35-yard gap between exact and order is the safety margin the rounding buys you, not waste.
Output · formula · meaning
| Output | Formula | What it means |
|---|---|---|
| Needed area | area × (1 + waste ÷ 100) | 1,430.00 sq ft — 1300 × 1.10. |
| Exact cubic yards | needed area × depth ÷ 324 | 17.65 — 1,430.00 × 4 ÷ 324. |
| Order | exact cubic yards rounded up | 18 cubic yards — 17.65 rounded up. |
| Coverage per yard | 324 ÷ depth | 81.0 sq ft per yard — 324 ÷ 4. |
| Area behind a target exact figure | target exact × 324 ÷ depth ÷ (1 + waste ÷ 100) | 1300 sq ft — 17.65 × 324 ÷ 4 ÷ 1.10. |
| Depth behind a target exact figure | target exact × 324 ÷ needed area | 4 inches — 17.65 × 324 ÷ 1,430.00. |
| Waste behind a target exact figure | (target exact × 324 ÷ depth ÷ area − 1) × 100 | 10% — (17.65 × 324 ÷ 4 ÷ 1300 − 1) × 100. |
Three things to check before you trust the number
First, measure the beds, not the garden: length times width for each bed, added together, with paths, lawn and patios left out. An outline that includes a path can overstate the area by a fifth and order a yard you never spread. Second, settle the depth before you order: 4 inches is a fresh-bed depth, while a top-up over last year mulch needs only 1 to 2 inches, and doubling the depth doubles the order. Third, keep the waste honest: 10% covers settling and spillage on ordinary beds, but a steep bank or a bed full of shrubs that shed mulch onto the lawn deserves 15%, and a flat open bed can run 5%.
Worked example
Area 1300 sq ft, depth 4 inches, waste 10%. Needed area: 1300 × 1.10 = 1,430.00 sq ft. Exact yards: 1,430.00 × 4 ÷ 324 = 17.65 cubic yards. Order: 18 cubic yards, rounded up. Coverage per yard at 4 inches is 324 ÷ 4 = 81.0 sq ft. Drop the depth to 2 inches and the exact figure falls to 8.83 yards, order 9; raise the area to 1400 sq ft and it rises to 19.01 yards, order 20.
Larch mulch lookup table
Every row below uses 10% waste, the same as the worked example: needed area is the bed area times 1.10, exact yards are needed area times depth divided by 324, and the order rounds the exact figure up to the next whole yard.
| Area (sq ft) | Depth (in) | Needed (sq ft) | Exact (cubic yards) | Order |
|---|---|---|---|---|
| 400 | 2 | 440.00 | 2.72 | 3 cubic yards |
| 550 | 3 | 605.00 | 5.60 | 6 cubic yards |
| 700 | 4 | 770.00 | 9.51 | 10 cubic yards |
| 850 | 3 | 935.00 | 8.66 | 9 cubic yards |
| 950 | 2 | 1,045.00 | 6.45 | 7 cubic yards |
| 1050 | 4 | 1,155.00 | 14.26 | 15 cubic yards |
| 1300 | 4 | 1,430.00 | 17.65 | 18 cubic yards |
| 1450 | 2 | 1,595.00 | 9.85 | 10 cubic yards |
| 1600 | 3 | 1,760.00 | 16.30 | 17 cubic yards |
| 1800 | 4 | 1,980.00 | 24.44 | 25 cubic yards |
| 2000 | 2 | 2,200.00 | 13.58 | 14 cubic yards |
| 2200 | 3 | 2,420.00 | 22.41 | 23 cubic yards |
| 2400 | 4 | 2,640.00 | 32.59 | 33 cubic yards |
| 2600 | 2 | 2,860.00 | 17.65 | 18 cubic yards |
| 2800 | 3 | 3,080.00 | 28.52 | 29 cubic yards |
| 3200 | 4 | 3,520.00 | 43.46 | 44 cubic yards |
Every branch, checked
1300 square feet at 4-inch depth with 0% waste gives 16.05 cubic yards exact, order 17 cubic yards. 1300 square feet at 2-inch depth with 10% waste gives 8.83 cubic yards exact, order 9 cubic yards. 1400 square feet at 4-inch depth with 10% waste gives 19.01 cubic yards exact, order 20 cubic yards. 1200 square feet at 4-inch depth with 10% waste gives 16.30 cubic yards exact, order 17 cubic yards. Each branch changes exactly one input, so the difference from 17.65 isolates that input.
The reverses, worked backwards
The area behind 17.65 cubic yards is 1300 sq ft: at 1200 sq ft the figures are 16.30 cubic yards exact, order 17 cubic yards, and at 1400 sq ft they are 19.01 cubic yards exact, order 20 cubic yards. The depth behind 17.65 cubic yards is 4 inches: at 3 inches the figures are 13.24 cubic yards exact, order 14 cubic yards, and at 5 inches they are 22.07 cubic yards exact, order 23 cubic yards — one inch either way moves the order by several yards, because depth multiplies the whole bed. The waste behind 17.65 cubic yards is 10%: at 5% the figures are 16.85 cubic yards exact, order 17 cubic yards, and at 15% they are 18.46 cubic yards exact, order 19 cubic yards.
What the defaults assume
The defaults assume one flat measurement of 1300 square feet, a uniform 4-inch layer, and 10% waste for settling and spillage. Real beds vary: a bed that is 4 inches at the centre and 3 inches at the edges averages closer to 3 inches than 4, so the honest use is to enter the average depth, or to split the beds by depth and add the orders. Zero square feet is the honest edge: 0.00 cubic yards exact, order 0. Negative area, zero depth and negative waste are rejected — none of them has a meaning for a mulch order.
Who uses this
A homeowner re-mulching the front beds with golden larch mulch: the calculator turns a tape-measure afternoon into a delivery order, and the lookup table checks the figure at a glance. A landscaper quoting a job: the waste line is the visible allowance for settling, so the quote and the delivery match. A garden centre clerk helping a customer: area, depth and waste are the only three questions, and the order is the answer. A community garden volunteer ordering for shared beds: splitting the beds by depth and adding the orders keeps one deep bed from eating the shallow beds budget.
Accuracy & limitations
The arithmetic is exact for the inputs entered; the judgement is in the inputs. An area that includes paths, a depth that is the deepest point rather than the average, or a waste figure that ignores a steep bank will each move the answer by exactly the amount of the error, on every yard. The model does not include delivery minimums, bulk-bag versus loose-yard differences, mulch compaction after rain, or the extra depth that settles in the first month — allow for those separately, and re-check the order when the measured area or the depth changes. This page is a calculation tool, not landscaping advice.
Cite this calculator
Larch mulch 1300 sq ft at 4-inch depth with 10% waste needs 1,430.00 sq ft, 17.65 cubic yards exact, order 18 yards. Calculator, plus 16-row lookup table. Source: Bright Side Kit, https://brightoolbox.com/larch-mulch-chart/, accessed 30 October 2026 (2026-10-30).
Frequently asked questions
Why does the order round up instead of to the nearest yard?
Because a short delivery leaves a bed unfinished: 17.65 yards ordered as 17 leaves 0.65 yards of bed bare in theory, and in practice the settling margin disappears, while 18 covers everything with 0.35 yards to spare. Mulch is delivered by the whole yard, so rounding up is the only order that finishes the job.
What depth should I enter for a top-up?
One to 2 inches over existing mulch, not the 3 to 4 inches of a fresh bed. A top-up entered at 4 inches overstates the order, and the extra mulch ends up piled against stems where it does harm, not good.
How do I measure an irregular bed?
Split it into rectangles, measure length times width for each, and add the rectangles. A curved bed measured as one big rectangle overstates the area; three or four smaller rectangles get close enough for an order.
Is 10% waste always right?
No — it is the ordinary-bed default. Flat, open beds can run 5%, and sloped, shrubby or awkward beds deserve 15%. The waste line is your allowance for settling and spillage, so set it from the ground you are actually covering.
What if my exact figure is a whole number, like 4.00?
Then the order equals the exact figure: 324 square feet at 4 inches with 0% waste is exactly 4.00 cubic yards, order 4. Rounding up changes nothing when there is nothing to round.
Can I use this chart for other mulch types?
Yes — the volume math is the same for every loose mulch, because a cubic yard covers 324 square feet at 1 inch whatever is in it. Only the product name changes; the area, depth and waste work the same way.