Our native plant garden has been installed at the Chimney Swift tower at Prairie Ridge. We chose to feature native plants because we want to show that there are many native species that make fine garden plants. Nurseries mass-produce exotic species such as Nandinas, English Hollies, and various privet species, but they could easily focus on native species instead. Native species are readily available from some nurseries, so there’s no reason you need to plant exotic species, especially if the exotic is an aggressive plant that can become an ecological menace.
Native species have several advantages and exotics have various detriments. The exotics mentioned above have become noxious weeds in the Triangle, whereas native species are a natural part of the environment. Many exotic species have no natural constraints here and spread out of control, crowding out native plants. A walk on nearly any greenway in the Triangle will illustrate this effect—Chinese Privet (Ligustrum chinense) and Japanese Stiltgrass (Microstegium vimineum) grow in dense monocultures along most greenways, frequently with no native shrubs or wildflowers in sight. The ability of another well-known exotic, Kudzu (Pueraria montana var. lobata), to smother other plants, even trees, in this region is legendary. As a result, many of our native wildflowers are declining, often reduced to hanging on in a few protected areas. Wildlife of all kinds is adapted to native species, and even though some exotics produce fruit that wildlife eat, most exotics tend to be shunned by wildlife and thus do not help wildlife at all. Insects on which birds depend for food are often highly specific in their food needs, with the result that they cannot feed on exotic plants, and thus these invasive plants cannot benefit birds that depend on insect food. From birds and mammals to pollinators such as bees and butterflies, wildlife species fare best in landscapes with only native species. In addition, if one is considering species to plant, it is important to remember that native plant species are perfectly adapted to the local soils and climate.
Audubon North Carolina maintains a website that provides reasons to grow native plants, information on native plants that are especially good for birds, exotic plants to avoid, and links to nurseries that specialize in native plants. The address is http://nc.audubon.org/conservation/bird-friendly-communities/bird-friendly-native-plants.
Here is some information about the species that we have selected for the garden at the Chimney Swift tower.
Fringetree (Chionanthus virginicus): The Fringetree has become a popular
ornamental. Its primary draw for humans is its flowers, which have long, white petals. During the springtime, a Fringetree can look like a big, fluffy, white ball because it blooms so profusely. It’s also fairly easy to grow and is rarely much affected by pests. Although it usually grows on wood edges and in swamps in the wild, it is quite happy as a lawn plant in full sunlight and it usually stays shrubby in cultivation. Although people grow it for its flowers, its fruits are popular with a wide range of birds, including Wild Turkeys. Fringetrees are either male or female, so it’s necessary to have both for fruit production.
Shrubby St. Johnswort (Hypericum prolificum): The Shrubby St. Johnswort
is a low-growing shrub that has become popular as an ornamental in recent years. Its biggest selling point is its flowers, which are bright yellow, with five petals and a bushy mass of stamens, and nearly an inch across. They’re pollinated by bumblebees and, because they usually grow in clusters, they can make the bush quite a showpiece when it blooms in spite of is short stature. Although another species of St. Johnswort is used as a homeopathic remedy for depression, there’s no solid proof of its effectiveness and the flowers are a far better reason to grow the plant. The name “St. Johnswort” comes from the fact that a European species usually bloomed around St. John’s Day, June 24. Wort (rhymes with dirt) was once the general English word for “plant,” and even though it’s been displaced by the Latin word plant, it lives on in numerous plant (or wort!) names.
Common Winterberry (Ilex verticillata): The Common Winterberry is one of a group of deciduous hollies with showy, red berries. Along with another
winterberry, the Possumhaw (Ilex decidua), it grows natively in the Triangle. Whereas the Possumhaw grows to become a small tree, the Common Winterberry remains a shrub and thus can be grown in a small garden. It’s not prickly or evergreen as the American and English Hollies are, but there’s an easy way to tell it’s a holly. Some plants have two growths called stipules at the base of each leafstalk. In many plants, the stipules are leafy, but in hollies, they’re reduced to blackish nubs that you might need reading glasses to see. All the hollies have stipules of this form. Like other hollies, winterberry bushes are either male or female, so you’ll need one of each to have a berry crop. Winterberry fruits, though poisonous to humans, are eaten by robins, mockingbirds, waxwings, and other fruit-eating birds during the winter.
American Beautyberry (Callicarpa americana): The American Beautyberry is
usually seen as a spindly shrub in woodlands. It makes an excellent ornamental, however, and is very easy to grow. It puts out clusters of small, pale pink flowers in spring, but its real selling point is its fruit. During the fall, its small, beady fruits, which grow in dense clusters, turn vivid purple when they ripen. When the berries are ripe, they are remarkably eye-catching. They ripen just as birds are migrating and can draw catbirds and Brown Thrashers that are moving south for the winter. Some Asian species of beautyberries are cultivated, but they have narrow leaves, whereas our native species can be recognized by its much wider, nearly round leaves.
Eastern Redcedar (Juniperus virginiana): The Eastern Redcedar is often one of the first trees to colonize an abandoned field. Its dark green, narrow form
stands out against other early succession trees such as Sweetgums. It is easily grown in yards as long as it gets full sunlight. Its soft, fragrant, red wood was the original wood used for pencils, and because it is rot-resistant, it makes good fenceposts as well. A redcedar fruit looks like a small, round, blue berry, but it’s actually a cone with the same basic structure as a pine cone except that it is soft and a little juicy instead of hard and woody. Fruit-eating birds such as robins, waxwings, and even Yellow-rumped Warblers are fond of the “berries.” The dense foliage of redcedars also serves as cover for many birds.
Red Buckeye (Aesculus pavia): North Carolina has three native species of
buckeyes. The Yellow Buckeye (A. flava) grows to be a large tree, but it is found only in the mountains. The Painted Buckeye (A. sylvatica) is usually shrubby and is restricted to the Piedmont, and it can be seen in many locations in the Triangle. The Red Buckeye (A. pavia) is mostly a small tree of the coastal plain, though it extends up the Cape Fear River valley to the Triangle area. It is the only buckeye with red flowers—our other species have greenish-yellow flowers—and it puts on a nice floral display in the spring that draws pollinators and makes it an attractive ornamental tree. All buckeyes have poisonous nuts, but squirrels can tolerate them, even though they generally avoid them until other nuts become scarce.
Sourwood (Oxydendrum arboretum): The Sourwood, or Sorrel Tree, is an
all-American tree. Whereas there are species of hickories, sassafrasses, and tuliptrees in Asia, and many trees such as oaks, pines, and birches are found as different species across the Northern Hemisphere, there’s only one Sourwood and it grows natively only in the United States. Although it can be grown in the open, it prefers some shade. It has some of the best fall color of any tree—bright pink when it grows in the shade and dark red in sunny locations. It’s best known as a honey tree, however. During the summer, it grows finger-like clusters of white, urn-shaped, sweet-smelling flowers that provide bees with summer nectar. Because of the way the flowers look, nurseries sometimes sell this species under the name “Lily-of-the-Valley Tree.”
Common Waxmyrtle (Morella cerifera): Our waxmyrtle, often listed under
the bookish name Southern Bayberry, is an evergreen large shrub or small tree. People commonly use it for hedges, and it adjusts well to being trimmed. It’s abundant on the Outer Banks, but it also grows wild in the Triangle. The leaves are fragrant when crushed or after a rainstorm and, when dried, can be used as a substitute for bay leaves. The waxy, gray fruits were once used to make candles. However, their greatest value is for birds. Yellow-rumped Warblers (the eastern race of which was formerly called Myrtle Warbler) depend on them to survive during the winter. If you plant Common Waxmyrtles, once they’re large enough to bear fruit, you’ll have Yellow-rumped Warblers from October until the berries run out.
Sparkleberry (Vaccinium arboretum): The Sparkleberry, or Farkleberry, is a
relative of blueberries that can grow to be a small tree, though it usually looks more like a large shrub. Unlike blueberries, it’s evergreen. It grows under partial shade and it’s often seen on rocky hilltop locations. The berries look very much like blueberries. They’re not juicy, but they have a pleasantly tart flavor and make an acceptible trailside nibble. Many kinds of wildlife also partake of the fruit. Only a few nurseries carry Sparkleberries, but their evergreen foliage, bird-friendly berries, and tendency to grow in a picturesque, gnarled shape make them well worth a search. Be sure to keep a Sparkleberry plant watered until it’s established, and after that it will be quite drought-tolerant.
Eastern Redbud (Cercis canadensis): The Eastern Redbud is one of the best-known ornamental trees in North Carolina. In early springtime, before other
trees have leafed out, otherwise inconspicuous redbud trees appear in their deep pink glory along our roads and freeways. Their color and the way they brighten the landscape, heralding the coming of spring, have made them a popular landscape plant. Specimens that are large enough can have every branch covered with the flowers, which by the shape of their petals show that they’re in the same family as beans and peas. What is not as widely known about redbuds is that they provide crucial nectar for the first butterflies that emerge in the spring.
Southern Arrowwood (Viburnum dentatum): This shrub has undergone
some taxonomic confusion. It was formerly considered to occur across much of the eastern United States, but now populations west of the Appalachians have been split off as another species, Indiana Arrowwood (V. deamii). Southern Arrowwood, when cultivated, makes a rounded shrub with a moderately dense growth habit. The twigs typically grow straight and perhaps were used for arrow shafts by Native Americans. The veins on the toothed leaves are also straight as an arrow. It has white flowers in the summer and small, black fruits in the fall that are eaten by various birds and small mammals. Like the fruits of other viburnums, each fruit contains one seed.
American Holly (Ilex opaca). The American Holly is popular for its evergreen
foliage and bright red berries. American Hollies are notoriously hard to transplant unless you find one as a seedling, but they can be grown in pots and then planted. They resemble the English Holly (Ilex aquifolium), which is a popular ornamental in Raleigh. English Hollies can be invasive, however. The easiest field mark for telling the two species apart is the glossiness of the leaves. American Hollies have what looks like a matte finish, whereas English Holly leaves are decidedly glossy, often looking like somebody poured glaze on them.