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plant this
not that
by Eva Rodriguez, education intern
Thousands of plants have been introduced to the United States from other parts of the world. Some have come here
accidentally in seed stock, while others were brought here intentionally for horticultural use. A small number of these
introduced plants have gotten a little too comfortable in their new environment. Because they have no native predators and
produce a lot of fruit and seeds that are efficiently dispersed, they are easily invading natural areas. The aggressiveness of
these invasive plants affects natural areas and wildlife by decreasing biodiversity, competing with native and rare plants, and
eliminating wildlife habitat and food sources.
Plant This, Not That features a list of native alternatives to a commonly used landscape plant that has become invasive. The
alternatives were chosen because their characteristics – form, flowers, fruit or fall color – are similar to that of the invasive and
fulfill the same landscaping need. Plants that are native to Ohio are recommended when possible as native species are generally
well-adapted to local climates and provide additional resources for wildlife. However, there are many non-native plants on the
market that are also non-invasive and possess great ornamental value.
The Invasive
Lonicera japonica ‘Halliana’ (Japanese honeysuckle vine)
Lonicera japonica ‘Halliana’ is a readily available cultivar of the infamous and
invasive Lonicera japonica (Japanese honeysuckle). L. japonica was introduced
into North America in the 1860s from Eastern Asia and Japan. The cultivar
‘Halliana’ was introduced by George Hall to Parsons’ Nursery in Flushing,
N.Y., in 1862 as a ground cover species along banks and rough terrain;
a single plant can grow to be more than 18 feet in length. Once it escaped
into the wild, it became a “most pernicious and dangerous weed” according
to E.F. Andrews in a 1919 issue of Torreya, which reported that “it is no
uncommon thing to see acres upon acres … buried under the rank growth of
this aggressive invader.”
Lonicera japonica flowers.
The Alternatives
Lonicera sempervirens (Trumpet honeysuckle)
Planting Lonicera sempervirens in place of the invasive Lonicera japonica is a far better
Lonicera sempervirens flowers.
choice for your home landscape and the local ecosystem. L. sempervirens is a woody
John D. Byrd, Mississippi State University, Bugwood.org
vine native to the southeastern United States. Due to this plant’s native range, it is
heat adapted and can easily survive Northeast Ohio’s humid summers. It is also one
of the tougher honeysuckle species; in addition to its tolerance of heat, it is deer resistant,
and drought tolerant, according to North Creek Nurseries.
L. sempervirens has vibrant orange to scarlet trumpet-shaped flowers, which is where it gets its namesake, trumpet honeysuckle. The
scentless, flowers bloom from mid-June to August and produce bright red berries in the fall. Both flowers and berries are showy and
colorful enough to see from a distance. If you can believe it, there are cultivars of L. sempervirens that have even more brightly colored
flowers. “There are so many cultivars now,” Tubesing said. “Some of them we even sell at the Arboretum’s Plant Sale in May.” In
addition to L. sempervirens’ horticultural value, this plant has wildlife value as well. The bright red flowers attract hummingbirds and
provide them with a sweet nectar meal. With L. sempervirens’ quick growth rate and similar characteristics to L. japonica, this better
behaved native honeysuckle will make a practical ground cover in the home landscape, and can be confined to a small trellis or fence
rather than running rampant. Examples of this plant can be found in the Paine Rhododendron Discovery Garden, the Display Garden
and the Holden Butterfly Garden.
Leslie J. Mehrnoff, University of Connecticut, bugwood.org
It is not difficult to imagine why L. japonica was brought into North America.
This vine is classically beautiful, with deep green summer foliage allowing
its fragrant, white trumpet-shaped flowers to stand out when they bloom
in early June. As the seasons change, L. japonica’s fall foliage is a brilliant
Lonicera japonica fruit and foliage..
bronze surrounded by striking black berries. Many invasive species and
Chris Evans, Illinois Wildlife Action Plan, Bugwood.org
cultivars lack wildlife value; however, this is not the case for L. japonica.
On the contrary, many birds and small mammals consume and disperse the large amounts of fruit this plant produces,
according to the U.S. Forest Service. While L. japonica helps provide habitat for birds and small mammals, because of the
dispersal of its abundant fruits, this plant can outcompete native plants in woodlands for space and resources. Its vigorous
growth behavior can lead to heavy infestations with the plant climbing up whole trees and over structures.
L. japonica will grow in almost any soil type and is difficult to eradicate once established in a woodland. Charles Tubesing,
The Holden Arboretum’s plant collections curator, recommends that there are many non-invasive alternatives to plant in
preference to L. japonica. Birds can disseminate the seeds, so planting it anywhere outdoors near woodlands were it has not
already been established leads to problems unless the fruit is removed before they ripen.
Clematis virginiana (Virgin’s bower)
It’s not an easy task to find a native vine as showy and beautiful as the
honeysuckles. However, Clematis virginiana’s beauty rivals the beauty of the
popular Lonicera species. C. virginiana is a native, perennial vine that is widely
available via mail order, and in some garden centers and nurseries. It has
scentless, frothy-white flowers on a vigorous, fast-growing vine. C. virginiana’s
blooming season is in June and short, lasting a little over a month, but when
it does bloom, it does so abundantly and elegantly. The blossoms are followed
by fluffy seedheads that are very attractive, adding an additional ornamental
quality to the plant. “It’s pretty in flower and pretty in seed,” said Roger Gettig,
director of horticulture and conservation.
C. virginiana is most commonly confused with C. terniflora (sweet autumn
clematis), its invasive Asian relative. An easy way to differentiate the two species
is to examine their leaf margins. C. virginiana’s leaf margins are toothed while
C. terniflora’s are smooth. Because of its rapid and smothering growth habit, C.
virginiana is best planted where it has a fence to climb and cover, and separated
from less vigorous plants.
Clematis virginiana flowers.
Wendy VanDyk Evans, Bugwood.org
Leaves
Spring 2015
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Lonicera japonica infestation. Chuck Bargeron, University of Georgia, Bugwood.org
Clematis virginiana. John D. Byrd, Mississippi State University, Bugwood.org
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