Shrubs, or bushes formed on numerous stems growing out of the soil, create garden interest through many seasons as they flower, produce berries and display rich foliage. Hundreds of species exist, each with numerous varieties. Grouped together, they can form fences or create garden areas. Shrubs can be planted together based on colour, texture and growth habits. Shrubs should also be grouped by needs -- such as sun or shade and hardiness zone.
Combining shrubs to create a well-balanced, unified landscape includes several design concepts. Foundation shrubs, which anchor or unify the house to the landscape, for instance, need to be an appropriate size. A very tall hibiscus, for example, would overwhelm a small house just as a low-growing juniper alone would be lost against a large house. Tall vertical shrubs, like lilacs, should be placed in front of a window. Tall shrubs should be planted behind small shrubs.
Shrubs are important in creating garden colour, which is one of the greatest challenges in gardening, according to landscape architect William H. Frederick. Yellow-green foliage -- like old gold juniper -- works well when combined with shrubs containing red, yellow and/or orange in blooms or foliage. Blue-green shrubs -- like Wilton's juniper and leather leaf mahonia -- and maroon bushes -- like Japanese Barberry and smokebush -- group well with red-yellow-orange colours or pink-lavender-purple.
Putting together shrubs with contrasting form and textures creates interesting groupings. Planting Scotch broom, with a vertical form and fine branches, together with bayberry, with a mounding habit and broad leaves, is an example. Fine-textured plants can be combined in a focal planting near a doorway or hard scape, points out William Frederick, while broad-leafed shrubs are better viewed from a distance.
In landscape designs, shrubs can unify a landscape by creating horizontal lines. Combining different shrubs by the same height, for example, throughout a landscape of trees, perennials and ground cover, creates a horizontal line that unites the landscape. It can be created by grouping, for example, horizontally branching shrubs like burning bush or double viburnum and planting them in areas throughout the landscape.