Trees provide dramatic vertical layering within the landscape and garden, shrubs are the primary way gardeners can diversity the garden horizontally. Shrubs are also a useful source for food and cover for wildlife on a smaller scale, often down to ground level.
Just as trees create shady microclimates in the landscape, shrubs provide cover for some smaller shade-loving plants. In natural plant communities, these beneficiaries include young trees conditioned to grow up in cover provided by shrubs.
The word shrub comes from an Old English word meaning brushwood. Not exactly flattering! Even lowlier is its variant scrub, one of whose meanings is anything undersized or inferior.
Humble beginnings or not, today there's nothing inferior about shrubs. Often standing midway in height between trees and flowers, shrubs provide a visual transition.
Some flowering shrubs attract birds with their fruit and some shrubs even provide colorful fall foliage rivaling any tree. Flowering shrubs are perhaps at their best when in bloom. Masses of blooms can stand alone as specimens used for focal points in the landscape. Many shrubs provide that first glimpse of mass color after a long winter of nothing but gray.
Most shrubs are deciduous, although rhododendrons, which are "broadleaf" evergreens, are welcome exceptions. But evergreens not grown for a floral display, like boxwoods and yews, can serve important functions, too, most notably as hedges. In particular, the Japanese Yew can be used in topiary design. There's a good example of a rather unique topiary garden using yews in Columbus Ohio. It's called Topiary Park. They have taken a famous painting by Georges Seurat and designed a park based on the painting.
There is great variety in landscape shrubs, both in terms of appearance and uses. Some landscape shrubs are compact, or even dwarfs. But others are tall enough virtually to be small trees and, in fact, may be just that in warmer climes. Some lose their leaves in winter, while other landscape shrubs are evergreen. Yet there is variation even amongst the different evergreen bushes. Uses for landscape shrubs include foundation plantings, formal hedges, informal privacy hedges and specimen plants.
Dense and twiggy shrubs are well suited to blending fences and buildings into the landscape to achieve a softened seamless appearance.
When pruning shrubs, take care not to shear off long-lasting berries and flower buds that promise a future food supply for birds.
Shrubs are invaluable in the garden. They impart shape, structure and substance to a design and provide a framework for the landscape. They have a variety of qualities that should be considered when making a purchase consider fragrant and color of blooms, fruits and shape and color of stems when dormant.
You should also consider rate of growth and eventual height and spread to determine if a particular shrub will fit in its intended site.
Since there are so many different shrubs to choose from, its important to select only those varieties suitable for your site.
It may be helpful when selecting new shrubs for your landscape to take into account the seasonal interest the new shrubs might provide. Planning a succession of blooms in the landscape is a good idea.
Spring flowering shrubs add not only new leafs after the long winter, but also soon come into bloom adding to the spring experience. Lilacs and forsythia are a good examples. Other good spring bloomers include salix melanostachys, jasminum, and daphne.
There are many summer flowering shrubs. Cinquefoil (Potentilla), Little leaf Lilac (Syringa microphylla) are good examples that provide bloom throughout the summer months from spring to early fall.
Fall is when many deciduous shrubs put on a show with their colorful foliage. Shrubs of special fall interest include Burning Bush (Euonymus alatus), Smoketree (Cotinus Coggygria), and the orange clusters of Firethorn (Pyracantha). Also worth noting is the attractive fruits of Viburnum that often last into winter.
Evergreen shrub foliage is probably the most notable of winter shrubs.