How to Landscape With Boulders

Overview

Landscaping boulders are a durable natural material used for centuries in natural garden designs around the world. Combined with trees, water features or plants on a terraced wall, boulders ground the garden with a solid, timeless look. Consider how landscape boulders set the tone in Japanese, Italian, English cottage and shady forest gardens with carefully placed outcroppings of native rock. Called hardscaping, including landscape boulders in the framework of your garden design can enhance the plants and other elements you choose.

Step 1

Choose boulder tones that blend in naturally with plant life in your area of the country or the specific design of your garden. Create the illusion of a desert rock garden, an Italian terrace or northern pine forest by combining boulders and plants from similar habitats.

Step 2

Bury accent boulders several inches in the ground for a natural look. Study rocks in nature or visit an arboretum for successful landscape ideas; natural boulders are not perched on top of the soil.

Step 3

Create an accent sculpture by combining a mountain-shaped rock, a flat-topped rock and a rounded medium height rock. This mimics the universally pleasing design of mountain, tree and lake.

Step 4

Place boulders in your garden for year-round interest. A large boulder with a flat top makes a bench for you or your pet, or a perch for wildlife. A boulders with a cavity on top creates a natural birdbath or butterfly drinking station.

Step 5

Create a visual division between a parking space and a yard with boulders. Line a path or entrance to direct traffic flow and transition between garden rooms with large landscape boulders, much like the lion sculptures on the famous steps of the main public library building in New York City.

Step 6

Choose rocks of similar size when building a border or wall. Landscape stores sell boulders of similar sizes on pallets.

Step 7

Dig a trench and bury the first course halfway under the ground. Place the sides as tightly as you can, rotating the boulders with a pry bar for a good fit.

Step 8

Offset boulder edges on each course. Maximize surface contact for strength when building a wall. Maintain a 25% setback angle for stability. Pack dirt behind the boulders and tamp with a tool as you build up your wall.

Tips and Warnings

  • Call the national utility hotline before delivery of your boulders. Do not place large boulders over sites where your underground utility hubs are buried.

Things You'll Need

  • Large or small landscape boulders

References

  • "Garden Design"; Sylvia Crowe; 1994
  • "University of Minnesota: Building Boulder Walls"

Who Can Help

  • 811: "Call Before You Dig"; Common Ground Alliance; 2010
Keywords: landscape rocks, landscape boulders, landscape wall, fieldstone boulders