How this landscape calculator works
A yard never has one bed. This landscape materials calculator keeps a running tally — the bed you're typing is always live in the total, and “Add bed” banks it and clears the form for the next one:
order = Σ beds ÷ 27 × (1 + allowance%) → rounded once to ¼ yd³
At the defaults — one 12 × 8 ft mulch bed at 3 in — the order is 1 yd³, about $40; the worked example below adds a second bed to show why the tally matters. The trick is that rounding happens once, over the summed volume, not per bed — which is exactly where ordering bed-by-bed quietly wastes a quarter to half a yard.
The materials you can tally here
One tally, one material, one delivery — pick the material and its density, bag size and default price all load together. Each also has a deep-dive page for the coverage charts:
- Mulch — 2 ft³ bags: the bed blanket; 2–3 in over fabric. Charts on the mulch calculator.
- Topsoil — 0.75 ft³ bags: the growing medium; 4–6 in where things root. The topsoil calculator goes deeper.
- Compost — 1 ft³ bags: the amendment, worked in 1–2 in. Priced on the compost calculator.
- River rock, pea gravel, sand — 0.5 ft³ bags: the mineral options; decorative stone runs on the river rock calculator.
The reason to tally rather than price each bed on its own page is the rounding. A supplier batches in quarter-yards and charges one delivery, so five small beds ordered separately mean five round-ups and, often, five trips or five delivery fees. Summed first, they round once and ride on one truck — the saving shows up on both the material line and the Saturday.
What depth should each material be?
Each material has its own working depth, and the tally lets you mix bed sizes but not materials — so set the depth to match whichever one you’re ordering:
- Mulch: 2–3 in — enough to block light without smothering roots.
- Decorative rock: 2–3 in, about twice the largest stone, over woven fabric.
- Topsoil: 4–6 in of workable depth where plants root.
- Compost: 1–2 in worked into beds, ½ in raked over lawns.
- Paver sand bed: 1 in screeded, under the pavers — the paver base calculator sizes the base below it.
How much landscape material per bed?
Table 1 is the working depth for each material — the number to set per bed before you tally; Table 2 is the 2026 bulk price range each one runs, the default the picker loads. Both are starting points: type your own depth and your yard’s quote straight over them.
| Material | Depth |
|---|---|
| Mulch | 2–3″ |
| River rock / pea | 2–3″ |
| Topsoil | 4–6″ |
| Compost (amendment) | 1–2″ |
| Paver sand bed | 1″ |
| Material | Range |
|---|---|
| Topsoil | $20–50 |
| Mulch / compost | $30–60 |
| Sand | $30–60 |
| Pea gravel | $40–90 |
| River rock | $70–130 |
How to tally beds for one order
- Measure every bed’s length and width; total odd shapes on the square footage calculator first.
- Pick the one material for the whole order — its density, bag size and price load together.
- Enter the first bed and its depth, then hit “Add bed” to bank it and clear the form.
- Keep adding beds; the running total sums every volume before the single ¼-yard rounding.
- Read the one order in yards, bags and dollars — and compare bulk against the bag count before you buy.
Worked example: mulch for a set of beds
Two beds of mulch at 3 in, tallied into one order — the whole reason to add rather than round each:
bed 2 = 10 × 4 × (3 ÷ 12) = 10 ft³
total = 34 ft³ ÷ 27 = 1.26 yd³ × 1.05 = 1.32 → 1.5 yd³
rounded separately = 1 + 0.5 = 2 yd³ · the tally saves ½ yard
Bed one alone rounds to 1 yd³; bed two alone rounds to 0.5 — order them apart and you buy 2 yards. Tallied first, the same 34 ft³ rounds once to 1.5 yd³. That half-yard is the tax on ordering bed-by-bed, and it grows with every bed you add.
What this landscape estimate doesn’t include
The tally sizes the loose material for one delivery. A finished bed needs a few things it doesn’t count:
- Landscape fabric. Woven geotextile under rock and mulch beds — priced by the ft².
- Edging. Steel, stone or poly restraint to hold the material out of the lawn.
- Delivery. One haul fee for the tallied order — the saving over multiple drops.
- Mixed materials. The tally is one material at a time; run rock and mulch as separate orders.
- Bed prep and labor. Sod removal, grading, and spreading the pile.
Landscape materials FAQ
How do I calculate landscaping materials?
Bed by bed: length × width × depth for each, sum the volumes, then round the total once. The default 12 × 8 ft mulch bed at 3 in is 0.89 yd³ — order 1 cubic yard (13 two-cubic-foot bags), about $40 bulk. Add every bed and the materials calculator keeps one running order.
How many yards of mulch or rock for several flower beds?
Enter the first bed, hit “Add bed”, and keep going — the tally totals all of them before the ¼-yard rounding, so five odd beds become one clean supplier order instead of five rounded-up ones. That alone typically saves a quarter to half a yard.
What depth should each landscape material be?
Mulch 2–3 in, decorative rock 2–3 in (twice the biggest stone), topsoil 4–6 in where things grow, compost 1–2 in worked into beds or a half inch raked over lawns. The depth chips cover the common cases; type anything else.
Should I order landscaping materials in bulk or bags?
The tally makes the call obvious: past about a yard, bulk wins on price — the bag count is shown so you can compare a pallet against a delivery fee. One drop for the whole tally beats bed-by-bed store runs on both money and Saturdays.
How much do landscaping materials cost?
Per bulk cubic yard in 2026, roughly: mulch $30–60, topsoil $20–50, compost $30–60, sand $30–60, pea gravel $40–90, river rock $70–130 — delivery extra. Picking a material loads its default price; type your quote over it.
How many yards of mulch for a 200 square foot bed?
At a 3 in mulch depth, 200 ft² is 50 ft³ — 1.85 yd³, ordered as 2 cubic yards with the 5% allowance, or about 27 of the two-cubic-foot bags. That is already past the point where a bulk drop beats bags on both price and effort, so order the yard.
Sources and standards
The tally is arithmetic; the numbers behind each material are the same ones the deep-dive pages use:
- One shared density set: mulch 800, topsoil 2,000, compost 1,000, sand and river rock ~2,700 lb/yd³ — matched across every material page.
- Matched bag sizes: mulch 2 ft³, compost 1 ft³, topsoil 0.75 ft³, rock and sand 0.5 ft³ — the standard retail bags.
- Round once, over the sum: supplier practice — waste and ¼-yard rounding applied to the whole order, not per bed.
- Editable prices: the 2026 ranges are defaults; your yard’s quote and delivery fee govern.
Embed this landscape calculator on your site
Run the landscape calculator on your own site, free. Paste the snippet where you want it; the visible credit link is the only condition.