Landscape Rock Calculator
Cubic yards, tons or bags of landscape rock for beds, borders and xeriscape coverage.
Quick estimating rule of thumb
For landscape rock: length (ft) × width (ft) × depth (in) ÷ 324 = cubic yards. Decorative rock is about 1.4 tons per yard. Use 2 inches for small stone, 3 to 4 inches for 1–2 inch rock. Add 10% for uneven beds and edge loss.
This landscape rock calculator turns bed length, width and depth into the cubic yards, tons or bags of decorative rock you need for a mulch-free border, a xeriscape bed or a rock garden.
Landscape rock is sold by size grade (often 3/8 inch up to 2–4 inch) and almost always by the ton. Larger grades need a deeper layer to hide the soil, which the depth input covers. For smooth creek stone specifically, use the river rock calculator; for #57 drainage stone use the crushed stone calculator.
How deep for full coverage
To hide fabric or soil, spread landscape rock at least twice the diameter of the largest stones: about 2 inches for small rock, 3 inches for 1–2 inch rock, and 4 inches or more for larger cobbles. Thin coverage looks patchy the first time it rains.
One cubic yard covers about 160 square feet at 2 inches, or 80 square feet at 4 inches.
Rock instead of mulch
Decorative rock does not break down, so you are not topping it up every season the way you do with wood mulch. It also sheds heat and does not feed the soil. Use it where you want permanent coverage and low maintenance, not where you want to improve planting beds over time.
Lay woven landscape fabric first, then the rock. Thin non-woven fabric tears under stone and weeds push through.
Ordering by the ton
A cubic yard of landscape rock weighs about 1.4 tons. Quarries sell by the ton; bagged rock (0.5 cu ft) only makes sense for small accents. Order about 10% extra for uneven beds and edge loss.
Common landscape-rock mistakes
Too thin for the stone size. Cover to at least twice the largest stone diameter or soil shows through after the first rain.
Skipping fabric. Without a woven geotextile, rock sinks and weeds seed in the dust.
Using rock where you wanted soil improvement. Landscape rock does not break down into organic matter the way mulch does.
Buying bags for a big bed. Past about 15 bags, a bulk ton delivered is usually cheaper.
| Material | lb / ft³ | tons / yd³ | Sold by | Typical use |
|---|---|---|---|---|
| Pea gravel (3/8″, rounded) | 100–105 | 1.35 | ton or yd³ | Paths, patios, dog runs, drainage |
| #57 crushed stone (3/4″, washed) | 100–105 | 1.35 | ton | Drainage, slab sub-base, French drains |
| 3/4″ minus / dense-grade | 105–115 | 1.45 | ton | Driveway base, paver base, road pack |
| Crushed concrete (RCA) | 100–110 | 1.35 | ton | Driveway base, structural fill (cheaper) |
| River rock (1–3″) | 95–105 | 1.40 | ton or yd³ | Dry creek beds, borders, xeriscape |
| Decomposed granite | 110–120 | 1.50 | ton | Paths, patios, natural-look driveways |
| Road base / Class 5 | 110–120 | 1.50 | ton | Compacted base under pavers, slabs, drives |
Frequently asked questions
How much landscape rock do I need?
Multiply area by depth and divide by 27 for cubic yards, then by about 1.4 for tons. A 100 square foot bed at 3 inches needs roughly 0.9 cubic yards, about 1.3 tons.
How deep should landscape rock be?
At least twice the size of the largest stones for full coverage: about 2 inches for small rock, 3 to 4 inches for 2-inch and larger.
How much does a cubic yard of landscape rock weigh?
About 1.4 tons (2,800 lb), similar to river rock and loose gravel.
How much area does a ton of landscape rock cover?
Roughly 110 square feet at 2 inches deep, or 55 square feet at 4 inches.
Is landscape rock better than mulch?
For permanent, low-maintenance coverage yes. For planting beds that need organic matter, wood mulch is better because it breaks down into the soil.
Do I need fabric under landscape rock?
Yes. Use a woven geotextile so weeds stay down and the rock does not sink into the soil. Avoid thin non-woven fabric.
How many bags of landscape rock in a cubic yard?
About 54 bags of 0.5 cubic foot. Past about 15 bags, bulk by the ton is usually cheaper.
What size landscape rock should I buy?
3/8 to 1 inch for paths and small beds, 1–2 inch for most borders, and larger cobbles as accents. Match depth to stone size so soil does not show through.
How much landscape rock for 200 square feet?
At 3 inches deep, about 1.85 cubic yards or 2.6 tons before the 10% allowance.
Landscape rock vs river rock?
River rock is the smooth, water-worn grade. Landscape rock is the broader retail label and may include angular or mixed decorative stone. Use the matching calculator for the product your yard quotes.
Can landscape rock replace mulch?
Yes for permanent coverage around shrubs and in xeriscape beds. Keep it pulled back from trunks, and do not use it where you want the soil to gain organic matter each year.
How much does landscape rock cost per ton?
Often $40 to $120 per ton delivered depending on colour and size, plus a haul fee. Enter your local price in the calculator for a job estimate.
Do I need edging with landscape rock?
Yes. Rock migrates without a hard edge: steel, aluminium, pavers or a cut trench along every border.