River Rock Calculator
Estimate the amount of river rock for your landscaping project. Enter the area dimensions and desired depth to get volume, weight, and cost for garden beds, dry creek beds, and borders.
River Rock Sizes and Uses
River rock comes in a range of sizes measured by diameter. Pea-sized (3/8 inch) river rock works for walkways and drainage. Small river rock (1 to 2 inches) is the most popular choice for mulch replacement in flower beds and around trees. Medium stones (3 to 5 inches) create attractive dry creek beds and borders. Large river rock (6 to 12 inches) serves as accent pieces, retaining wall faces, and heavy-duty erosion control. The rounded, smooth shape of river rock allows water to flow freely, making it excellent for drainage applications.
Installation and Maintenance Tips
Prepare the area by removing existing vegetation and grading the soil for drainage. Lay commercial-grade landscape fabric to block weed growth, overlapping seams by 6 inches. Spread river rock evenly to your target depth. Unlike mulch, river rock never decomposes and rarely needs replenishment. Maintenance involves occasional rinsing with a hose to remove dust and leaf blowing in fall. Avoid river rock directly against your house foundation if your soil is clay-heavy, as it can trap moisture. A 6-inch gap with gravel against the foundation is better for drainage.
Frequently Asked Questions
How deep should river rock be?
For landscaping beds, 2 to 3 inches of river rock is typical. Dry creek beds look best at 4 to 6 inches deep. Always install landscape fabric underneath to prevent weed growth.
How much does river rock cost per ton?
River rock costs $50 to $150 per ton depending on size and color. Small 1-3 inch stones are cheapest. Large 3-5 inch or specialty colored river rock costs more.
What size river rock should I use?
Use 1 to 2 inch stones for ground cover and beds, 3 to 5 inch for dry creek beds and borders, and 6+ inch for accent features and erosion control.