What Is a Good Shrub for a Windbreak?
Taller Evergreen Shrubs
Evergreen shrubs provide good wind protection year-round. Dense, tall evergreens can provide very effective protection for distances at least twice their height. Kim Powell of the North Carolina Cooperative Extension recommends sasanqua camellia (Camellia sasanqua), evergreen holly (Ilex spp.) and viburnum (Viburnum), which reach heights of 6 to 12 feet. Each has ornamental as well as utilitarian value.
Shorter Evergreen Shrubs
Some windbreak designs call for shorter shrub rows interspersed with trees and taller shrub rows. For these, slower-growing evergreens, such as some boxwoods (Buxus sempevirens spp.) may be more desirable. Dwarf species of evergreens, such as hollies, as well as lower-growing evergreens, such as some juniper cultivars, may be used in the same manner.
Taller Deciduous Shrubs
Shrub dogwoods properly maintained with routine prunings create dense thickets that can easily grow 10 feet tall or higher and often have colorful bark for winter interest. Some native species, such as red-osier dogwood (Cornus sericea) and silky dogwood (Cornus amomum), are particularly desirable for wildlife habitat, as well. Deciduous hollies, such as possum haw (Ilex decidua) and winterberry (Ilex verticillata), and viburnums, such as arrowwood (Viburnum dentatum) and highbush cranberry (Viburnum opulus var. Americanum), can also form windbreaks.
Shorter Deciduous Shrubs
Shorter deciduous shrubs planted near trees reinforce the density of a windbreak at ground level. Lilacs (Syringa vulgaris) and shrub roses, such as Rosa rugosa, are examples of flowering shrubs that make attractive windbreaks.
Windbreak Construction
Choosing shrubs suitable for your climate and growing conditions is just the first step in planting your windbreak. In order to put your shrub choices to best use, consider their placement and spacing in relation to the structures or plantings you wish to shelter, as well as their proximity to each other and other elements of your wind protection. Ideally, your windbreak shrubs should create a continuous, dense barrier placed to deflect prevailing winds. You may need multiple rows of shrubs planted with trees for greatest effectiveness.
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