Walls serve a number of purposes in gardens, sometimes functioning as major structural elements and other times as minor decorative touches. High walls enclose spaces, creating secluded gardens. Landscape retaining walls stabilize the grade, preventing erosion and creating attractive tiers. Even low, decorative walls serve a purpose, dividing the space in interesting ways and creating visual boundaries.
Scavenged Stone Privacy Wall
Build a tall privacy wall out of irregular scavenged stone or a variety of different sizes of commercial stone. Use large stones at the bottom and smaller stones toward the top of the wall. This will give it a rugged, uneven look and will add additional height to the wall, particularly if the top is above eye level.
Use a low wall to create a garden in your patio. Build a circular flagstone wall 1 to 2 feet high in the middle of your patio. It should be on top of bare earth or gravel and made out of stones with a different colors and textures to contrast with the rest of your patio. Use wide pavers at the top to create a ledge for sitting beside the garden. Fill the area inside the stone wall with soil to create a raised garden bed. Grow flowers, specimen trees or other plants. Create a low, decorative wall or border around the outside of the patio using the same stone you used for the garden bed to give the patio more definition.
Treated Wood Wall
Stone walls have exceptional durability, but a treated wood wall will last for many years and add warmth that a stone wall can't. Use treated wood retaining walls to stabilize moderate grades. Add a layer of bark mulch to the garden behind the wall to decrease erosion and harmonize with the color of the wood. For a smaller, decorative wall, dig a trench around a garden and place short wooden posts or blocks in the ground. The natural browns of the wood will create an understated boundary around the garden.