They mark boundaries, keep children and pets safely inside, and provide comfort and privacy.
Barriers can be inviting or intimidating.
Psychologically, low barriers (1m to 1.2m) denote privacy, but are inviting.
Tall fences or walls (1.8m to 3m) tell people to keep out.
Fences and walls should flow with the landscape.
Don't let them dominate your property.
Plantings make barriers appear less conspicuous.
If you don't want an enclosed space, use short sections of fencing spaced intermittently.
A section or two around a patio or other private space may be enough to add contrast and create interest.
A wide range of fencing is available in wood, metal, plastic and recycled materials.
Here are some ways that I have built fences and walls:
> Crushed gravel base: The best method for do-it-yourself fence installation because it is done dry, without concrete, and can hold fenceposts firmly.
Wooden fences are especially susceptible to rot at ground level.
Concrete can hold moisture around a post and encourage decay.
To set a wooden post, place the post 0.6m into the ground, digging a hole with a posthole digger or auger.
Tamp coarse crushed gravel firmly in the hole around the post to keep the area well drained.
This will also hold the pole solidly in place and keep it from rotting.
Use a level to keep the post plumb - that is, perpendicular to the ground.
> Concrete base: Sometimes it's not practical to use stone because it will not set the post securely enough.
Concrete can be poured to any thickness and depth depending on the sturdiness required.
Metal poles should be anchored in concrete for chain-link fences.
Tightly stretch the fence from one post to another, after the concrete has hardened, and only if it withstands the tension.
Walls add beauty to gardens, and low ones can double for seating, although they do not provide as strong a spatial enclosure as a fence.
Using them to retain banks and slopes will add strength to designs.
They can turn slopes into multilevel terraces.
Grade changes are interesting elements, and retaining walls add horizontal stability.
Such walls must be able to withstand hundreds of kilograms of pressure from the weather pounding down on the soil.
Mortar masonry walls built to function as retaining walls must be built on concrete footings.
Masonry walls mortared together must not move or lean.
They need to be perfectly plumb. This rule applies to all mortared walls.
Start these structures on concrete footings. They should be poured on undisturbed soil. Footings average 60 to 70cm deep.
The following materials make excellent retaining walls and are conducive to dry installation:
>Concrete block retaining wall systems: Most lock together and lean into the bank slightly, with plenty of natural weep holes and provisions for drainage stone.
Search the internet using the words "garden walls".
> Dry-stack walls: Easiest to maintain.
If rocks fall down, the pieces that fell down can easily be picked up and put back together again.
Stone stacked without mortar is versatile.
It fits the landscape and offers natural weep holes that can be planted.
Use rocks of a similar shape, and take time to assess how each one will fit its space.
Careful laying of stone is noticeable in the finished product. - Los Angeles Times-Washington Post Note: Building consent is sometimes required before fences can be installed.
Call your local council to find out rules on height and other requirements.
- Lerner is author of Anyone Can Landscape (Ball 2001). Contact him through his website, www.gardenlerner.com
