“Boxwood honeysuckle” is a common name for certain Lonicera species that resemble true boxwood (Buxus species) due to their shrubby growth and small leaves. While some Lonicera species are not problematic, others, such as Lonicera microphylla and Lonicera nitida, are a concern due to their ecological impact.
Understanding Boxwood Honeysuckle
Plants commonly known as “boxwood honeysuckle” are deciduous or evergreen shrubs within the Lonicera genus, part of the Honeysuckle Family. Lonicera microphylla is a deciduous shrub growing 1 to 3 meters tall. Its simple, middle-green leaves are arranged oppositely on the stems. In spring, it produces small, greenish-yellow, funnel-shaped flowers, followed by small, red berries in summer. This species is native to Central Asia.
Lonicera nitida, an evergreen shrub native to China, grows 1.2 to 1.5 meters tall. It has small, dark green, glossy leaves and creamy white flowers that appear in pairs, followed by bluish-purple berries.
Distinguishing from True Boxwood
“Boxwood honeysuckle” plants are botanically distinct from true boxwood (Buxus species). A primary difference is their leaf arrangement: honeysuckles have opposite leaves, growing directly across from each other on the stem. True boxwood species, however, have alternate leaves, staggered along the stem.
Another distinguishing feature is the pith, the spongy tissue in the center of a stem. Invasive honeysuckle species typically have hollow stems with a brown pith in older branches. True boxwood has a solid pith. Honeysuckle flowers are often tubular and in pairs, while boxwood flowers are inconspicuous. Their fruits also differ, with honeysuckles producing berries and boxwoods forming small capsules.
Why Boxwood Honeysuckle is a Concern
Many shrubby honeysuckle species are considered invasive in various regions, particularly in North America. These non-native species, such as Amur (Lonicera maackii), Morrow’s (Lonicera morrowii), and Tatarian (Lonicera tatarica) honeysuckles, were often introduced as ornamental plants or for erosion control. They spread rapidly, outcompeting native vegetation by forming dense thickets that reduce light and nutrient availability for other plants.
This aggressive growth leads to monocultures, reducing biodiversity and altering natural habitats. Honeysuckles leaf out earlier in spring and retain their leaves later into fall than many native species, giving them a competitive advantage. Birds consume the berries, dispersing seeds widely into natural areas like forests and roadsides. Some invasive honeysuckles also exhibit allelopathy, releasing chemicals that inhibit the growth of nearby plants. Their dense growth can also provide ideal conditions for ticks, increasing their population in invaded areas.
Managing Boxwood Honeysuckle
Managing boxwood honeysuckle requires consistent effort. For small, young plants, manual removal by pulling them out of the ground is effective. Remove as much of the root system as possible to prevent regrowth. Larger shrubs can be cut down to the stump, with the cut surface then treated to prevent resprouting.
Mechanical removal, such as cutting stems with loppers or chainsaws, reduces above-ground growth, but regrowth is common without further treatment. Chemical control using herbicides like glyphosate or triclopyr applied to cut stumps is an effective method for larger plants. Non-chemical alternatives for stumps include covering them with black plastic to starve the plant of light, which can take several months. Proper disposal of plant material, especially berries, is important to prevent further spread.
Recommended Alternatives
Replacing boxwood honeysuckle with native or non-invasive plant alternatives supports local ecosystems and prevents further spread of invasive species. For a dense, evergreen hedge similar to boxwood, inkberry holly (Ilex glabra) is an excellent native option, offering glossy green leaves and dark berries that attract birds. It can be pruned to maintain a desired shape and size.
Other suitable native shrubs include various species of viburnum, such as arrowwood viburnum, which provide habitat and food for wildlife. Ninebark (Physocarpus opulifolius) is another versatile native shrub with attractive foliage, flowers, and textured bark, adaptable to a range of conditions. Native trumpet honeysuckle (Lonicera sempervirens) offers vibrant tubular blooms that attract pollinators without the invasive tendencies of its non-native relatives. American elderberry (Sambucus canadensis) is a fast-growing, adaptable shrub that provides both shelter and food for birds and pollinators.