How deep should river rock be?

The depth should be at least twice the largest stone dimension. That means 2 inches for 1-inch rock, 3 to 4 inches for 2-inch rock, and 6 inches for large cobble.

How much does river rock cost?

River rock is the most expensive common landscape stone at $55 to $130 per ton delivered, or roughly $75 to $175 per cubic yard depending on colour and size.

Do I need fabric under river rock?

Yes. Landscape fabric stops weeds coming up and keeps the rock from sinking into the soil, which otherwise buries a decorative bed within a few years.

Landscaping

River Rock Calculator

River rock is priced by the ton like other stone but costs two to three times as much, so over-ordering is expensive. This calculator uses river rock's own density and depth guidance, including the deeper coverage that larger cobble sizes require.

What you'll need

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FANTIAN 10 lbs Pea Gravel for Landscaping, 3/8 Inch Pebble Stone, Colorful

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33ft. Galvanized Steel Landscape Edging (10-Pack) – 40" Metal Edging for Landscaping with 11 Stakes, Hammer-in Metal Landscaping Edging for Yard Pathway & Flower Beds – Lawn Edge for Garden Design

$69.99

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HongWay 500 Pack 6 Inch Landscape Staples, Garden Staples Pins Galvanized 11 Gauge Ground Stakes Yard Lawn Staples for Turf Landscaping Fabric Fence Tent Irrigation Tube Outdoor Decorations

$37.99

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FANTIAN 20 lbs Natural River Rocks, 2-3 Inch Pebbles Rocks for Landscaping

$39.99

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Prices as of Sep 25, 2026, 6:18 PM UTC. Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.com at the time of purchase will apply to the purchase of this product.

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Frequently asked questions

How deep should river rock be?: The depth should be at least twice the largest stone dimension. That means 2 inches for 1-inch rock, 3 to 4 inches for 2-inch rock, and 6 inches for large cobble.
How much does river rock cost?: River rock is the most expensive common landscape stone at $55 to $130 per ton delivered, or roughly $75 to $175 per cubic yard depending on colour and size.
Do I need fabric under river rock?: Yes. Landscape fabric stops weeds coming up and keeps the rock from sinking into the soil, which otherwise buries a decorative bed within a few years.