This article is almost a continuation of my article on form. In my article on form I stressed that when using form to unify a garden, it is best to not focus on individual plants, but I have to admit that it is the growth patterns of individual plants which create the forms that most gardens are composed out of, so this article is about the shapes of plants and how they can be used to create a garden that is a unified work of art.
Trees are the tallest elements in most gardens, so they are the dominant element. The shape of a tree against the sky can set the mood for an entire garden. As the trees mature, their influence over the garden becomes stronger and stronger, so it is best to think about the mature shape of trees before planting them.
During the 18th century many Cedars of Lebanon were planted on English estates. These trees, with their strongly horizontal or tabulate branching pattern are now unifying features in the gardens that have developed around them. The distinctive form of the cedars is easy to recognize from every part of the garden, so even though each room in the garden may have it's own theme, they all feel like they are part of one garden.
Cedars of Lebanon are not fast growing and they only have tabulate structure at maturity, but these patriarchs of English gardens have a lot to teach us about how to use shape to unify a garden. When trees are small, they aren't very impressive, so we tend to plant too many of them. Trees with striking shapes are most effective when viewed against the sky, not as a part of a mass of trees. If you can practice self-restraint and patience, your garden may only need one large tree which has a striking growth pattern.
If you are creating a new garden in an area without trees, you should look at the shapes of mature trees. Many deciduous trees have cloud-like shapes maturity. Cedars and many pines are tabulate at maturity, but when they are young they have the cone like shape typical of conifers. Other conifers retain this cone-like shape throughout their lives. Some trees have a columnar (or fastigate) shape, they are best used as exclamation points in the landscape, although they can be used like columns in formal gardens.
