University of Minnesota Extension
www.extension.umn.edu
612-624-1222

Extension is expanding its online education and resources to adapt to COVID-19 restrictions.



Extension > Extension in your Community > Le-sueur > Master Gardeners > Articles > Bush Honeysuckle: A Shade Plant with Shady Lookalikes

print icon email icon share icon

Bush Honeysuckle: A Shade Plant with Shady Lookalikes

Invasive Bell’s honeysuckle. Photo by: Leslie J. Mehrhoff, University of Connecticut

Every day I arrive to work in Le Center I’m greeted by a row of honeysuckles. These plants have thrived in an usually inhospitable area; a significant amount of residual heat from the parking lot in the summer, and powerful polar winds from the west. Their yellow flowers always seemed to attract nearby pollinators, and even induced a panic in the courthouse when more than a few wasps happened to stop by one summer morning. When I would visit Iowa to see my parents, however,  an entirely different outlook about honeysuckles emerged. With an axe in one hand and a spray bottle of potent herbicide on the other, I was fighting a scourge rather than a landscaped plant.

These invasive species of honeysuckle encroached on a nearby prairie from the wooded edge. Once, that border was filled with clusters of beautiful cup plants (Silphium perfoliatum). I enjoyed seeing the cup plants holding rainwater—with the occasional tree frog swimming in it. Now, I am greeted with yards of gnarled bushes, similar in density to buckthorn (Rhamnus spp.)

So, to grab the axe or the camera? To start, these invasive honeysuckles are almost exclusively in the Lonicera genus. These include: Amur (L. maackii), Tatarian (L. tatarica), Bell’s (L. x bella), and Morrow’s (L. morrowii) honeysuckle. There are also native species part of Lonicera but are much more like vines than a shrub/small tree.

The invasive honeysuckles were initially brought to the US by well intentioned landscapers and gardeners. Given how comfortable these plants were to a variety of environments, they were chosen for soil stabilization and wildlife interest. The shrubs were certainly successful in the latter, as birds gulped down the berries, spreading them across the US into places such as the wooded lot of my parents. Once planted, honeysuckles would start fast, leafing out early in the spring and holding onto said leaves into the fall. For example, an Iowa State University colleague of mine shared a photo where a Tatarian honeysuckle was leafing out on March 4th! This greater time gathering sunlight helps outcompete other native plants such as gooseberries or currants (Ribes spp.)

To inform your axe or camera decision, a quick way to ID an invasive honeysuckle is to split an older, bigger branch of the plant and look for a partially hollow stem with a brownish pith. They will also be an upright woody shrub as well, not a vine or a prostrate bush. To control, an herbicide treatment containing triclopyr is best. However, one with glyphosate (i.e. RoundUp) can also be used. Please read the label for any chemical applications, some products which contain triclopyr or glyphosate are not suitable for treating honeysuckles. That label will also inform you about the prefered method of application. I have personally had some luck with cut-stem treatment, otherwise called a “hack and squirt” method. Essentially, you prune or “hack” the plant down to a few inches off the ground, then spray a mixed solution of your chosen herbicide.

All this toil makes it even more annoying that the exact same soil stabilization and wildlife “benefits” could already be had by a native relative, the northern bush honeysuckle (Diervilla lonicera). This plant’s taxonomy is a bit confusing, as it is currently listed in the relatively new Diervillaceae family. Originally, it was in the Caprifoliaceae family, the same one which the invasive honeysuckles currently reside. To make matters worse, some people still call the invasive species “bush honeysuckles” as well. Northern bush honeysuckle flowers certainly do look similar to their invasive lookalikes, but are yellow for most of their life before turning reddish, as opposed to white or pinkish white of the Lonicera plants. Northern bush honeysuckle also likes to grow low to the ground, and does not form a thick brush which is difficult to get through. Similar to the exotic Lonicera species, northern bush honeysuckle can thrive in full shade to partial sun. It likes its soil a little coarser or well drained, but can still hug steeper hill sides with few problems. They are also hardy to Zone 3, attract native pollinators and birds, and without the environmental damage of Amur, Tatarian, Morrow’s, or Bell’s honeysuckles.

Works Cited: