The Real Benefits of Shrubs in Landscaping (And Which Ones Work Best in Tennessee)
Shrubs give you more bang for the buck from landscape plants than almost any other plant group․ They block the sun during summer months and the resulting air conditioning costs‚ screen your property much more quickly than a fence‚ slow down erosion on sloped land‚ and provide wildlife with food and habitat․ Unlike annuals that need to be replanted every year‚ and herbaceous perennials that die back in winter‚ an ideal shrub works for you year-round for decades․ For gardeners in any part of Tennessee's Zone 6b to 7b range‚ there are hundreds of shrubs that thrive in clay soils and summers' humidity without a gardener's constant care․
Let's go into just what a shrub can do for a property in this area‚ and some favorites here․
Energy Savings You Can Actually Measure
Dense evergreen shrubs on the west and northwest sides of a house block the low afternoon sun in summer and winter wind exposure․ The Department of Energy estimates that good foundation plantings can reduce the cost of cooling houses by 15-25%․ It is basic thermodynamics: A shrub with thick‚ glossy leaves that remain year-round is a far better shield against solar heat than a deciduous shrub that drops most of its leaves at the hottest time of year․
Nevertheless‚ the customary choice here is boxwood shrubs‚ which hold their dark green foliage all year long‚ turning a slightly bronzed cast in winter‚ but such color changes are merely a sign of the normal process of hardening off with the cold․ They bloom in spring with small clusters of fragrant yellow-green flowers‚ usually one female and up to six males․ The plants must be spaced 2 to 3 ft (0․61 to 0․91 m) away from foundations (but not closer‚ lest they collect moisture) and 2 to 4 feet (0․61 to 1․22 m) apart from each other‚ depending on the cultivar․ Boxwoods tend to grow slowly‚ around 3-6 inches per year‚ and thus require very little trimming to keep shape‚ except for a light trim in late spring․
Privacy and curb appeal without waiting a decade
Unlike almost any other evergreen‚ the arborvitae solves the privacy problem quickly: the column is dense and upright‚ with a naturally rounded base․ The evergreen fan needles remain in color well through the winter months‚ unlike some other evergreen species which turn either olive or brown․ In Tennessee‚ spring-planted arborvitae grow well‚ with 1-2 feet growth in the second and third years․ Therefore a three-foot hedge can be expected to grow 8 to 10 feet high in four to five years․ Space plants three to four feet apart for a dense hedge; wider spacing is acceptable if individual plants are to be presented․
The male flowers appear in spring and release yellow pollen‚ though it won't create an unsightly mess on your driveway if you choose a location close to the pavement․ Female flowers turn into erect small fruit․ The smell of cut or crushed leaves is sweet‚ with a slight spiciness; it is one of those little details that make a landscape more than a landscape․
How To Keep Deer Out
There is a large deer population in Tennessee․ Deer damage can be troublesome to any suburban homeowner whose property borders a wooded lot․ Viburnum shrubs are deer resistant․ Deer dislike the smell and taste of viburnum foliage‚ and often do not continue munching these shrubs after initially sampling them․ Even so‚ not without beauty‚ a range of white‚ pink or ivory flowers bloom from early spring to late summer․ Although the leaves of some species are smooth-edged and oval‚ other species have serrated-edged leaves․ Leaf veins are prominent in some species․ Foliage can be burgundy or gold in the autumn․
Viburnum is both helpful to butterflies and other pollinators and unpalatable to deer‚ so you don't have to sacrifice attracting the good bugs to keep the bad ones at bay․ It grows best in full sun to partial shade and in well-drained soil; in Tennessee's heavier clay soil‚ mix a few inches of compost into the soil at planting time․
Building an Actual Wildlife Habitat
If you enjoy attracting wildlife to your garden‚ elderberry is one of the best shrubs to grow․ Its flat-topped clusters of small‚ white flowers (scientifically speaking‚ these flower arrangements are known as umbels) are fragrant and have five petals‚ and appear each spring․ These umbels mature into purple black fruit about four weeks after bloom‚ with berries less than a quarter inch across containing three to five seed-like stones․
Elderberry can occupy a space of 12 feet by 10 feet at full growth․ Plants should either be given this space or pruned fairly hard every year or two․ Elderberry responds very well to such treatment and often grows even more profusely․ In return you have a shrub that is the sustenance for an unusually large number of animals․ The song and game birds eat the berries; deer and bears browse the leaves and berries; and the insects are attracted to the flowers throughout spring․ If you have a back corner of your property that is more wild than manicured‚ consider elderberry․
What This Means for Your Landscape Planning
Don't be like most homeowners who select shrubs only for their looks and figure out their purpose later․ What role will a shrub play in your landscape? Block cold winds? Save energy? Screening? Deer resistance? Wildlife-friendly? Perhaps erosion control on a slope? Choose your shrub based on need first‚ and then think of how it looks․ A property using diverse needs looks layered and purposeful anyway: boxwood as a foundation shrub around the house‚ arborvitae as a screen along the property line‚ viburnum along the edge of a patio where deer become obnoxious‚ and elderberry in an out of the way spot at the back of the yard․
At TN Nursery we grow and ship the shrubs that do best in the Southeast: boxwood‚ arborvitae‚ viburnum and elderberry․ We know what survives and thrives in Tennessee clay soil and humidity‚ not just what looks good in a photo․ Whatever your goals for privacy‚ reserves of water‚ or wildlife habitat‚ there is very likely a shrub that will do what you want‚ and doing some research to pick the right one saves years of replanting and reworking the landscape․
