Landscape Rock Calculator
Enter bed dimensions to calculate landscape rock needed.
Landscape Rock Formula
Enter bed length, width, and rock depth. The calculator converts to cubic yards and tons based on average landscape rock density.
Understanding Landscape Rock
Landscape Rock Types and Coverage
Landscape rock is a permanent ground cover that eliminates mulch replacement costs. Unlike organic mulches, rock does not decompose, fade, or blow away. The initial cost is higher, but the lifetime value is superior for arid climates and low-maintenance properties.
| Rock Size | Coverage at 2 in | Coverage at 3 in | Weight per CY |
|---|---|---|---|
| Pea Gravel (3/8 in) | 162 sq ft | 108 sq ft | 2,700 lbs |
| River Rock (1-3 in) | 130 sq ft | 90 sq ft | 2,700 lbs |
| Lava Rock (3/4 in) | 162 sq ft | 108 sq ft | 1,000 lbs |
| Decomposed Granite | 162 sq ft | 108 sq ft | 2,600 lbs |
| Mexican Beach Pebbles | 100 sq ft | 70 sq ft | 2,800 lbs |
Installation Best Practices
- Prepare the base: Remove existing vegetation, grade for drainage, compact the subgrade.
- Install edging: Steel or aluminum edging prevents rock migration.
- Lay fabric: Overlap seams by 6 inches and secure with landscape staples every 24 inches.
- Spread rock: Apply in a uniform layer at the target depth. Rake to level.
Landscape Rock vs. Mulch: Cost Comparison
Rock costs - per cubic yard vs. - for mulch. However, mulch requires annual replacement. Over 10 years, rock saves 40-60% compared to annual mulch replacement. Rock is the economical choice for permanent beds.
Landscape Rock Calculator FAQ
Measure the area in square feet, multiply by depth in feet, and divide by 27 for cubic yards. For 500 sq ft at 3 inches: 500 x 0.25 / 27 = 4.63 cubic yards. Add 10% for irregular shapes.
Use 2 inches for small decorative rock and 3-4 inches for larger rock. Deeper layers provide better weed suppression and prevent fabric from showing.
Pea gravel and crushed gravel at - per cubic yard. River rock runs -. Specialty stones like Mexican beach pebbles cost -. Local quarry products are always cheapest.
Most landscape rock weighs 2,400-3,000 lbs per cubic yard. Lava rock is approximately 1,000 lbs due to its porous volcanic structure.
Yes. Without fabric, weeds grow through within 1-2 years. Use non-woven geotextile fabric (not plastic sheeting) for best results.
No. Remove existing mulch first. Mulch decomposes under rock, creating soil where weeds thrive. Start with bare, graded soil, install fabric, then add rock.