What does 685.46 cubic yards of pea hull mulch mean?
It means a 67300 square foot bed, once the 10% waste allowance is added, needs 74,030.00 square feet of cover at 3 inches deep — 18,507.50 cubic feet, which is 685.46 cubic yards. Because mulch is sold by the whole yard, you order 686 cubic yards: the exact figure sits 0.54 yards below the next whole yard, so the order carries 0.54 yards of headroom for spillage and uneven ground. At 3 inches, one cubic yard covers 108.0 square feet, so the same bed at 2 inches would need only 456.98 yards, and at 4 inches it would need 913.95 yards.
Output · formula · meaning
| Output | Formula | What it means |
|---|
| Area needed | area × (1 + waste ÷ 100) | 74,030.00 sq ft — 67300 × 1.10. |
| Volume in cubic feet | area needed × depth ÷ 12 | 18,507.50 cubic feet — 74,030.00 × 3 ÷ 12. |
| Exact volume | area needed × depth ÷ 324 | 685.46 cubic yards — 74,030.00 × 3 ÷ 324. |
| Order quantity | round exact volume up to a whole yard | 686 cubic yards — the next whole yard above 685.46. |
| Coverage per yard | 324 ÷ depth | 108.0 sq ft per yard — 324 ÷ 3. |
| Area behind a target volume | target volume × 324 ÷ depth ÷ (1 + waste ÷ 100) | 67300 sq ft — 685.46 × 324 ÷ 3 ÷ 1.10, rounded. |
| Depth behind a target volume | area needed × depth ÷ 324, solved for depth | 3 inches — the depth that turns 74,030.00 sq ft into 685.46 yards. |
| Waste behind a target volume | target volume × 324 ÷ depth ÷ area − 1, as a percent | 10% — the allowance that turns 67300 sq ft into 74,030.00 sq ft. |
Three things to check before you trust the number
First, measure the bed honestly: length times width for each bed, added together, with L-shaped beds split into rectangles. A guessed area moves the order by the same percentage as the guess. Second, keep the depth honest: pea hulls are sturdy and fibrous, so they settle into a soft layer that holds moisture well, but even a firm layer thins as it breaks down and the thin spots need topping up through the season. Third, do not skip the waste allowance on pea hull: even well-laid pea hulls blow about at the edges, and spillage and uneven ground still eat into the load, so the 10% allowance is the difference between finishing the bed and running short with the truck already gone. The headline order of 686 yards carries 0.54 yards of headroom, which covers ordinary spillage on a bed like this one. The pea hulls themselves are hulls left after the pea harvest — the mulch comes from pea plants, not from timber.
Worked example
Area 67300 sq ft, depth 3 inches, waste 10%. Area needed: 67300 × 1.10 = 74,030.00 sq ft. Exact volume: 74,030.00 × 3 ÷ 324 = 685.46 cubic yards. Order: round 685.46 up to 686 cubic yards. Drop the waste to 0% and the exact volume falls to 623.15 yards, order 624; raise the waste to 5% and it is 654.31 yards, order 655; raise it to 15% and it is 716.62 yards, order 717. Drop the depth to 2 inches and it falls to 456.98 yards, order 457; raise it to 4 inches and it climbs to 913.95 yards, order 914. Depth moves the answer faster than waste does, because every inch adds a full layer across the whole bed.
Pea hull mulch lookup table
Every row below applies 10% waste to the area first, then divides by 324: yards = area needed × depth ÷ 324, rounded up to the next whole yard for the order. Find your bed size and depth, read across, and order the last column.
| Area (sq ft) | Depth (inches) | Area needed (sq ft, 10% waste) | Exact (cubic yards) | Order |
|---|
| 300 | 2 | 330.00 | 2.04 | 3 cubic yards |
| 300 | 3 | 330.00 | 3.06 | 4 cubic yards |
| 600 | 2 | 660.00 | 4.07 | 5 cubic yards |
| 600 | 3 | 660.00 | 6.11 | 7 cubic yards |
| 800 | 3 | 880.00 | 8.15 | 9 cubic yards |
| 800 | 4 | 880.00 | 10.86 | 11 cubic yards |
| 1100 | 2 | 1,210.00 | 7.47 | 8 cubic yards |
| 1100 | 3 | 1,210.00 | 11.20 | 12 cubic yards |
| 1300 | 2 | 1,430.00 | 8.83 | 9 cubic yards |
| 1500 | 3 | 1,650.00 | 15.28 | 16 cubic yards |
| 1600 | 3 | 1,760.00 | 16.30 | 17 cubic yards |
| 1600 | 4 | 1,760.00 | 21.73 | 22 cubic yards |
| 1800 | 2 | 1,980.00 | 12.22 | 13 cubic yards |
| 2200 | 3 | 2,420.00 | 22.41 | 23 cubic yards |
| 2600 | 3 | 2,860.00 | 26.48 | 27 cubic yards |
| 3200 | 2 | 3,520.00 | 21.73 | 22 cubic yards |
Every branch, checked
A 67300 square foot bed at 3-inch depth with 0% waste gives 623.15 cubic yards exact, order 624 cubic yards. The same bed at 2-inch depth with 10% waste gives 456.98 cubic yards exact, order 457 cubic yards. A 67200 square foot bed at 3-inch depth with 10% waste gives 684.44 cubic yards exact, order 685 cubic yards. The same bed at 4-inch depth with 10% waste gives 913.95 cubic yards exact, order 914 cubic yards. Each branch changes exactly one input, so the difference from 685.46 isolates that input.
The reverses, worked backwards
The area behind 685.46 cubic yards is 67300 sq ft: at 67200 sq ft the figures are 684.44 cubic yards exact, order 685 cubic yards, and at 67400 sq ft they are 686.48 cubic yards exact, order 687 cubic yards. The depth behind 685.46 cubic yards is 3 inches: at 2 inches the figures are 456.98 cubic yards exact, order 457 cubic yards, and at 4 inches they are 913.95 cubic yards exact, order 914 cubic yards — one inch either way moves the order by about 228.48 yards. The waste behind 685.46 cubic yards is 10%: at 5% the figures are 654.31 cubic yards exact, order 655 cubic yards, and at 15% they are 716.62 cubic yards exact, order 717 cubic yards.
What the defaults assume
The defaults assume a flat 67300 square foot bed, a uniform 3-inch layer, and a 10% waste allowance. Real pea hull beds are rarely simple rectangles: paths and tree trunks eat into the area, and pea hulls at the edges blow into the lawn, so measure the planted area only and keep the waste allowance on sloped ground. Zero square feet is the honest edge: 0.00 cubic yards exact, order 0. A depth of zero or below, a negative area, or a negative waste allowance is rejected, because none of them describes a real bed.
Who uses this
A gardener dressing beds and paths with pea hull: the 67300 square foot headline is a large garden bed or a long drive, and the table covers everything from a 300 square foot border to a 3200 square foot yard. A landscaper quoting a pea hull job: the waste column protects the quote, and the order column is the number given to the supplier. A homeowner laying pea hull on a path: the 3-inch rows are the bed depths, and the 2-inch rows are the path depths. A community garden coordinator splitting a bulk delivery: each plot reads its own row, and the orders add up to the truckload.
Accuracy & limitations
The arithmetic is exact for the inputs entered; the judgement is in the inputs. A guessed area, a depth measured before the pea hulls settle, or a skipped waste allowance will each move the answer by exactly the amount of the error, every load. The model does not include hull washing at the edges, delivery minimums, or the gaps between pea hulls — a supplier may sell only in whole yards or charge extra below a minimum, so confirm the order quantity with the supplier. Pea hulls are safe around most garden plants, but a thin fresh layer can scatter in wind, so top up established beds through the season rather than laying one thick layer and leaving it. This page is a calculation tool, not landscaping advice.
Cite this calculator
Pea hull mulch 67300 sq ft at 3-inch depth with 10% waste needs 74,030 sq ft, 685.46 cubic yards exact, order 686 yards. Free calculator, plus 16 rows. Source: Bright Side Kit, https://brightoolbox.com/pea-hull-mulch-chart/, accessed 2 November 2026 (2026-11-02).
Frequently asked questions
Why does the table apply waste to the area first?
Because waste is lost cover: spillage, scattering and uneven ground mean you need more covered area than the bed measures. Adding 10% to the area, then converting to yards, keeps the waste in the same units as the bed. Applying it after the conversion gives the same number here, but the area-first order keeps the table readable.
How deep should pea hull mulch really be?
Three inches is the standard bed layer on this page, and 2 inches suit paths and top-ups. Pea hulls are sturdy and fibrous, so a 3-inch spread settles quickly, though the hulls still break down over time; if thin spots appear, top them up rather than re-laying the whole bed.
Does pea hull mulch introduce weed seeds?
Pea hulls are organic, so a load can carry a few weed seeds; weeds can still root in the dust and debris that collects on top of it, so use fabric underneath and clear the debris. This calculator prices volume only and does not judge the gardening choice.
What if my bed is not a rectangle?
Split it into rectangles, measure each, and add the areas before entering the total. A circle uses radius times radius times 3.14. Guessing one number for an irregular bed is the most common reason orders come up short.
Why order 686 yards when the exact figure is 685.46?
Because mulch is sold by the whole yard, and 685.46 rounds up to 686 — the order carries 0.54 yards of headroom for spillage and uneven ground. That headroom is the buffer the exact figure does not have.
Can I use this chart for other mulch types?
The volume math is the same for any loose mulch — area, depth and waste convert the same way — but settling and coverage differ by material. Pea hulls break down readily, so use the pea hull rows for pea hull and the matching chart for stone or wood chips.