People frequently have more trouble with trees than any other part of the garden. If they like trees, they tend to plant too many trees. If they don't like trees, they tend to plant too few. It is important to consider why you might need trees, and then choose the appropriate number, type and sizes to suit your requirements.
Trees are used for the following reasons:
- Screen wind Wind will go over or around very dense vegetation. Wind goes through, and is slowed by less dense plantings.
- Screen noise Don't expect a complete barrier to noise. Plants reduce volume, but they don't completely stop noise.
- Screen fumes If you are beside a major road or factory, trees are essential to keeping air quality reasonable in your backyard.
- Hide ugly views Canopies can cut out ugly views (eg. tip sites, factories or unkept neighbouring properties).
- Provide privacy Plant wherever people are going to be able to see in.
- Create a visual link with adjacent areas If there is a treed area just outside your property, plant some trees adjacent to those plantings, but on your property. This creates one clump of trees which starts on your property, then extends beyond the boundary, giving an illusion of your property being bigger than it actually is.
- Create an ecological link with nearby areas. If you plant trees which supply food and shelter for nearby wildlife, you will find that wildlife will move into your property.
- Frame views If you have a valuable distant view (eg. mountains or the ocean), plant trees either side of the line of view to enhance and direct your attention towards that view.
- Provide features in the garden Large well formed trees when planted alone in a lawn or amongst small plants, will create an impression of grandeur which draws the eye. Smaller trees have the same effect when they provide a contrast in colour (ie. in foliage of flower), or texture against whatever is around them.
- Provide shade Shade is important, to protect other plants, and to provide a more comfortable atmosphere for people. Too much shade can deter plant growth, restrict the movement of fresh air and lead to water problems (because the ground does not dry out).