How to Build a Landscape Berm: Create Natural-Looking Mounds for Drainage and Design

A berm is a sloped mound of soil—often with fill material (sand, debris, rubble) at its core—that redirects drainage, adds elevation, and creates planting opportunities. Unlike island beds (floating in lawn for aesthetics), berms integrate naturally into the landscape for functional and visual purposes.

Building a Berm

1. Outline shape; remove grass
2. Add fill material to excavated area
3. Pack soil around fill, tamping firmly as you build
4. Slope gradually outward; peak off-center for natural look
5. Water to settle; tamp again to eliminate sinkholes
6. Plant if desired

Berm vs. Island Bed

• Island beds: Any shape, viewed from all sides, typically half as wide as viewing distance, aesthetic focus
• Berms: Usually curved, functional (drainage, elevation), peak off-center, follow land contours

Design Guidelines

• Length 4–5x height; height typically 18–24 inches
• Crescent shapes look most natural
• Blend transitions gradually—no "speed bump" effect
• Edge with stone/plants to prevent erosion
• Plant for year-round interest: drier-tolerant on top, moisture-loving at base
• Consider microclimates: south/west faces warmer; north/east cooler
• Mulch with shredded wood (resists washing)

Berms enhance landscapes naturally when designed with the land's flow.