JULY : honeysuckle : Lonicera japonica

Scientific name: Lonicera japonica

Suggested pronunciation: luh-NIS-er-a juh-PON-ih-kuh

Cultivar: Lonicera japonica ‘Halliana’ (hall-lee-AY-na)

Common names: honeysuckle, Japanese honeysuckle, Hall’s honeysuckle, Hall’s Japanese honeysuckle, woodbine

Family: Caprifoliaceae – honeysuckle. Suggested pronounciation: cap-ree-foh-lee-AY-see-ee

USDA Zone: 4 – 9 (Santa Fe is in Zone 6B)

Note: In this article the mention of the name, Japanese honeysuckle, also infers the name of the cultivar, ‘Halliana’ (or Hall’s honeysuckle) and common name of honeysuckle.

Article by Janice Tucker

Fragrance is a gift that nature seems to bestow upon those of us who lovingly tend to the health and welfare of plants in our care. But we’re really just incidental recipients of the perfume emanating from flowers and leaves. That aroma is primarily targeted to lure pollinators, especially those that are active at night. As dusk descends, plants such as the Japanese honeysuckle (Lonicera japonica) intensify their fragrance. Scent may be one method some plants use to let the night pollinators know that the nectar bar is always open but it is also a major reason for including them in our gardens.

Native to east Asia, the Japanese honeysuckle is now found in many parts of the world. According to the U.S. Department of Agriculture and other reputable sources, it was introduced to the United States in 1806. Dr. George Rogers Hall (1820-1899)* was an American physician who lived in Yokohama, Japan for several years. Dr. Hall had an avid interest in Japanese plants. Upon his return to the United States in 1862, he brought a collection of several Japanese plant specimens to Parsons & Company Nursery in Flushing, New York. Among those plants was a horticultural variety of the Japanese honeysuckle that became known as Lonicera japonica ‘Halliana’, or Hall’s Japanese honeysuckle. Most of the plants he brought home also honor Dr. Hall with the ‘Halliana’ cultivar name. But the honeysuckle eventually caused the biggest uproar.

Although the cultivar was originally planted as a garden ornamental, it soon became popular as an ideal plant for erosion control in natural areas. However, when it got a toe hold onto disturbed ground, things turned ugly. It was planted in environments that catered to its then-unknown invasive tendencies. Unfortunately those traits did not take too long to manifest themselves. The dense growth aggressively spreads, smothering other plants in its path. The climbing vines can choke small trees and shrubs. Fire can destroy above ground growth but a hardy root system will ensure a comeback. Controlling it is difficult at best and eradication has proven to be almost futile. Southern and eastern states as well as some mid-western areas in the U.S. consider this plant a scourge on the landscape. Indiana and New Hampshire have banned it and the Missouri Botanical Garden calls it a “dreadful weed”. Anyone who moves from one of those affected regions to Santa Fe may gasp at the very idea of featuring the Japanese honeysuckle as a home garden selection. Please read on. There’s another side to this plant.

Santa Fe’s drier climate, high elevation and not-so-rich soil tends to tamp down this honeysuckle’s domineering tendencies. Even here it exhibits a healthy growth habit but can be contained to keep overbearing behavior at bay. And  the mix of the white and golden flowers scattered over the pretty green foliage is an attractive addition to the home garden.

An evergreen (in Santa Fe), perennial vine, the Japanese honeysuckle blooms from late spring into autumn. Smooth margined, oval leaves cover the stems in an opposite arrangement. The blossoms are positioned in pairs at the leaf axils with two on either side of the vine. The strongly fragrant, usually white flowers turn a golden-yellow as they mature. The nectar increases in quantity and tastes sweeter in the older flowers. The first blooms appear toward the inner portion of the plant, with the more recent blossoms at the tip end. They are short-lived, but with so many new blooms occurring every day, the spent flowers are hardly noticeable. The fruit emerges as plump, green berries that ripen into a shiny black. Only some of the fruit contain seeds. A variety of birds, deer and small mammals feast on the berries, which facilitates the plant’s spread. Its dense growth provides a secure habitat for furry critters and a nesting location for birds. Moths, bats, butterflies, bees, other insects and birds -particularly hummingbirds-flock to the honeysuckle to partake of its nectar.

By employing both asexual and sexual propagation, the Japanese honeysuckle goes all out to ensure its existence. Asexually, rhizomes, suckers and runners extend the growth area, which is considered to be manageable in our Santa Fe environment. The sexual propagation is rather fascinating, beginning with pollination. Plants know their pollinators and have evolved over the years to oblige their most frequent visitors. Each plant has its own design to promote fertilization. The honeysuckle applies every tool in its kit to entice pollinators. The fragrance and flower structure are important contributors to the vital phase of the plant’s sexual propagation.

The flowers first open at night and continue to remain open – day and night – until they fade. Therefore, pollination is active 24/7. A pollinator’s olfactory senses perk up when detecting the honeysuckle’s sweet, tantalizing fragrance, which is stronger at night. The scent leads the nectar-seeking critter to the source that holds the promised treat. It is welcomed by a tubular, wide-opened, two-lipped flower that exposes the throat where the nectar is stored. Of course the hungry visitor will head straight toward the throat to get at the sugary liquid. At one point during its visit – perhaps as it exits the flower – the pollinator will brush against the anthers at the tips of lengthy, spindly stamens that span from the throat to beyond the petals. An anther will tap a bit of pollen onto its guest before it leaves on its way to a neighboring flower. When it arrives at the next food stop and before partaking of another nectar helping, the pollinator will deposit the pollen it just received onto the stigma affixed atop a long, slender style, thus fertilizing the flower. And so it continues from flower to flower. A win-win trade: Food for fertilization.

A sunny location and well-drained soil are the main planting requirements. It will grow in partial shade, but try to stick with sunny areas since an overly shady spot usually results in more foliage and fewer flowers. And flowers are a must if fragrance and attracting pollinators play a role in selecting the Japanese honeysuckle. Water well after planting to establish the roots, but do not let the soil become soggy. After that, it only requires moderate watering. This plant already has an innate taste for vigorous growth, so forget the fertilizer. Be aware that some pruning maintenance is required to keep the plant groomed and on its best behavior. Because the honeysuckle mostly produces flowers on new growth, winter or early spring is the best time to give it a serious pruning. This timing will avoid shearing off any flowering vines. In spring and summer just clip off any stray tendrils to keep it looking its Sunday best.

In choosing the location, consider what you want the plant to do. If deciding to use it as a ground cover be sure there is plenty of space and commit to keeping those suckers, runners and rhizomes in check. Training the vines to climb on a structure is fairly easy and the vine is quite happy to accommodate those efforts. It can eventually become a dense hedge when trained along a fence. The twining vines can soften an adobe or stucco wall or turn an unsightly post into an attractive, living column. Be sure that the supporting structure is sturdy as the vine will become heavy as the years go by. Please avoid allowing the vines to encircle a tree trunk. That would eventually kill the tree.

Linda Churchill, the Head Gardener for the Santa Fe Botanical Garden at Museum Hill in Santa Fe New Mexico, points out that the Hall’s honeysuckle (Lonicera japonica ‘Halliana’) serves as a living entrance to the Garden. She says, “It was chosen to soften the entrance with a vigorous green upright-growing plant that emphasizes the entrance and is also fragrant for at least a few weeks. It’s not fussy and doesn’t require a lot of water or chemical inputs to grow well.” She said that it does require cutting back every few years but it has not invaded any natural areas. My 22 years of  personal experience with this plant echos Linda’s comments about care and maintenance.

The generic, Lonicera, honors German botanist-physician and author, Adam Lonitzer (also spelled Lonicer) (1528-1586). Swedish botanist-physician Carl Peter von Thunberg (1743-1828) spent many years studying and collecting plants in east Asia and particularly in Japan. He is credited with naming the Lonicera japonica. The specific, japonica, means, “of Japan”. The apt definition of the vernacular, honeysuckle, is derived from the Old English, “denoting tubular flowers, which are sucked for their nectar.” It is assumed that the common name of woodbine refers to the plant’s climbing tendency to wrap around woody shrubs and tree trunks.

The sense of smell is a powerful trigger to a past emotion or memory. It has been reported that Japanese honeysuckle can mentally transport someone back to a time in childhood or to evoke a certain sentiment when inhaling its scent. If there is a honeysuckle near you, go for a stroll in the gathering dusk. Take a deep breath to be rewarded by the perfumed air… and perhaps an unexpected but pleasant trip down memory lane. While the fragrance may be meant to entice pollinators, we take nothing away by savoring it too. And how sweet it is.

 Thanks to Helen Woody and Jeanne Gozigian for proofreading this article.

* The birth year for Dr. George Rogers Hall is uncertain. Sources consulted stated 1820, 1821 and 1826. The date cited in this article is taken from Page 5 of Stephen A. Spongberg’s “The First Japanese Plants for New England,” Arnoldia – the Arnold Arboretum of Harvard University. Citing information is listed below.

Sources Consulted and/or Cited:

“Adam Lonicer’s Herbal”. Botany at the Edward Worth Library. 2020. web. 01 May 2020.

Balogh, Anne. “Growing Heavenly Honeysuckle Vines: Growing a Non-Invasive Honeysuckle Plant”. Garden Design. 2020. Web. 21 May 2020. Retrieved from: https://www.gardendesign.com/vines/honeysuckle.html

“Carl Peter Thunberg”. Wikipedia: The Free Encyclopedia. Wikimedia Foundation, Inc. 25 Feb. 2020. Web.  25 Feb. 2020. Retrieved from: https://en.wikipedia.org/wiki/Carl_Peter_Thunberg

“Japanese Honeysuckle”. Forest Invasive Resource Center. Eastern Region State and Private Forestry, US Forest Service. Web. 22 May 2020. Retrieved from: http://www.nifatrees.org/Resources/Documents/Invasives/japanese-honeysuckle.pdf

Kurtz, Cassandra M.; Hansen Mark H. 2015. “An assessment of Japanese honeysuckle in northern U.S. forests.” Research Note NRS-202. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station. 5 p. Accessed 23 May 2020. Retrieved from: https://www.fs.fed.us/nrs/pubs/rn/rn_nrs202.pdf

Letherman, Anna D. “Ecological Life-history of Lonicera japonica Thunb”. Doctoral dissertation: University of Tennessee. 11 Aug. 1955. Web. 22 May 2020. Retrieved from: https://trace.tennessee.edu/utk_graddiss/1626

“Lonicera japonica ‘Halliana’”. Plant Finder. Missouri Botanical Garden. Web. 25 Feb. 2020. Retrieved from: http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=245393

“Lonicera japonica ‘Halliana’”. Garden Explorer. Santa Fe Botanical Garden. Web. 01 May 2020. Retrieved from: https://santafebotanicalgarden.gardenexplorer.org/taxon-482.aspx

“Lonicera japonica Thunb.” SEINet Portal Network. 2020. http//:swbiodiversity.org/seinet/index.php. Accessed on 12 May 2020.

Spongberg, Stephen A. “The First Japanese Plants for New England”. Arnoldia – the Arnold Arboretum of Harvard University. 1990. Web. 23 May 2020. Retrieved from: http://arnoldia.arboretum.harvard.edu/pdf/articles/1990-50-3-the-first-japanese-plants-for-new-england.pdf

Taft, David. “Why the Sweet Scent of Japanese Honeysuckle Signals Trouble”. N.Y.C. Nature, The New York Times. 24 Jun. 2016. Web. 05 Dec 2020. Retrieved from: https://www.nytimes.com/2016/06/26/nyregion/why-the-sweet-scent-of-japanese-honeysuckle-signals-trouble.html

Walsh, Colleen. “What the nose knows”. Science & Technology – The Harvard Gazette. 27 Feb. 2020. Web. 23 May 2020. Retrieved from: https://news.harvard.edu/gazette/story/2020/02/how-scent-emotion-and-memory-are-intertwined-and-exploited/