One way to add interest to your garden is by constructing a retaining wall. Behind this wall, you can plant a lawn or flower bed. Although building a retaining wall requires some planning and effort, they are actually not that difficult to build.
When planning your wall, make sure that it is strong enough to hold up the earth, but porous enough to allow for drainage. Many retaining walls are built from stone, held together with either dirt or cement between the stones.
In building your wall, be sure the base is sunk into the ground, ideally about 6 inches deep. Ideally, the width of the base should be at least a quarter of the wall’s height.
Every 24 inches or so, and about 6 inches from the lower ground level of the wall, you should install drainage pipes. If your wall is porous enough, you may not need these pipes. But, especially if you are using mortar to hold your wall together, drainage pipes are necessary.
If you are building a wall with soil between the stones, you may be able to start at the ground level, instead of sinking the wall into the soil, although it is better if you do start below the ground level. The easiest way to build your wall is to choose local stones, with larger ones for the main stones and smaller stones to fill in the holes. You should use smaller stones near the top of the wall. Try to make the side of the wall facing out as level as possible, ensuring an attractive appearance. Don’t use stones with round surfaces, as they will be hard to fit together into a structurally sound wall. No spaces should be left; they should be filled in with packed dirt or smaller stones.
When building the overall wall, make sure it slopes back slightly against the soil it is retaining. This will help give you wall strength. You can slope it as much as 5 or 6 inches back for every foot of height, although you do not need to slope it this much.
Once you have built your retaining wall, you can also use it as a wall garden. You can plant smaller plants in the soil between the stones. You can also plant flowers with strong roots, which will also help keep your wall strong as well as adding color. There are many different varieties of flowering plants which would be suitable for your wall.
If you are building a mortared or concrete wall, the construction will be somewhat simpler, as the mortar forms a tighter bond. You should mix 1 part Portland cement and 2 parts sand, coating the top of each stone to add the next layer. The areas between large stones can be filled with smaller stones. Mortared walls are much more permanent than those built with earth.
Concrete walls are even stronger than those built with mortar. However, you need to build forms for the concrete, which can be complicated. Concrete walls can be thinner than rock walls, especially if the concrete is reinforced when building landscape river walls.
No matter which method you choose, the top of your wall needs to be protected. You can use broad, flat stones on the top of your wall. Slate makes an excellent choice for this.