I enjoy musicals and have long been captivated by the title of the Rogers & Hammerstein tune Getting to Know You from The King and I -- the song title has meaning well beyond the musical storyline. I will employ it here to expose a weed that vexes me and other Midwest gardeners. This nemesis is called creeping Charlie (Glechoma hederacea) but it is not the only plant referred to by that common name. Moreover, it should not surprise you that this ubiquitous weed has several other monikers, like just Charlie. I particularly like the name sneaking weed because it fits the behavior of this insinuating nuisance. Additionally, while the reason for using creeping is obvious, and justified, I am not certain why the name Charlie was at some point applied. Nor could I find an answer other than the suggestion that it was just alliteration. Perhaps its origin is in military jargon, based on their phonetic alphabet. During the Vietnam conflict the Viet Cong were referred to as the V-C (Victor Charlie) thus Charlie could be the shortened version used to refer to an (or any) enemy. -- By the way, I find it more than curious that like with Korea in the 1950s, the U.S. Congress never officially designated the Vietnam action a war. In fact, there have been no such designations since WWII. The Constitution grants Congress the sole power to do so. Further, lost among all the associated Vietnam horror was the massive ecological devastation, technically referred to as ecocide, much of it from the herbicide Agent Orange which was applied indiscriminately and far in excess of the recommended concentration -- one of the worst examples of our ongoing ruination of Nature as well as our capacity for barbarism. Again, shame on us. FYI, Vietnam is among our most biodiverse areas -- think paradise. OOPS again, one of the many Mad Botanist faults is his common digression :)
A familiar and never-ending chore for gardeners is hunting for and trying to dispatch weeds, preferably before they have a chance to reproduce, thus become established, and hopefully learning from the experience. A good hunter gets to know his/her prey (e.g., what it likes and what it does not like in order to discover where it lives {its haunts} as well as when it is expected to be present, and vulnerable).
A member of the mint family (Lamiaceae), Charlie is an aggressively invasive aromatic evergreen herbaceous perennial that thrives in moist shaded areas. It can be a lawn problem, especially if there is a sprinkler system. I favor fragrant plants and am not alone in enjoying the unique smell produced when mowing a lawn containing this weed. Creeping Charlie is a Eurasian native but has naturalized around the world, spread in part by humans who sometimes use it as a salad green. Yes, it is edible. It has other ethnobotanical uses, too, but I will not elaborate since I do not want to promote its spread. The plants have a green to purple square stem (see pic), more purple in dry location, and the plants will be smaller there. Charlie's opposite leaves are round to kidney-shaped (reniform) with a scalloped margin. The leaves are typically 1-1.5 inches in diameter, but in optimal conditions, such as around the margin of my compost bin, they may approach or exceed three inches. The younger leaves often have a less rounded (more subacute) apex and the plants are stoloniferous (have a horizontal above ground stem rooted at nodes, like false strawberry and periwinkle) which makes them particularly difficult, dare I say essentially impossible, to completely eradicate manually. You will notice a popping sound and snapping sensation when pulling. You will also notice that the pulling is frustrating since the damn stems break easily, especially if and when the ground is dry. Any missed rooted segment will restart the spread. BEWARE, it loves mulch, especially wood chips -- an example of my Getting to Know You (creeping Charlie). When extracting Charlie from wood chips oftimes the entire plant can be lifted (no fragmentation) only to discover numerous chips attached to and dangling from the nodal roots. If so, I pitch or compost the whole assemblage for fear of recontamination.
The visual appeal of this vining weed is such that the species is sometimes grown as a hanging pot ornamental. There is even a curious variegated form. Charlie is available for sale online, but if you buy it you are a fool. Depending on where you live, Charlie is almost certainly already somewhere or all over your property. I would not want to invite any form of this thug onto my place. -- And know this, if you are unable to admit to the beauty, to see it as a separate element, say from origin (nativity) or weediness (think violets, various smartweeds and composites) then you need to work on being more objective.
Here are some more Getting to Know You comments regarding this mint -- by the way, the mint family has many members notorious for their tendency to spread (e.g., lemon balm and spearmint). In addition to covering the ground, Charlie is an opportunistic climber, although it lacks special vining morphology other than that the young terminal portion of the plants are often vertically oriented. I have found Charlie climbing the interior of shrubs, even some low branched coniferous trees, ascending up two to three feet before surfacing to the light where it can more or less enshroud the host plant exterior and where it produces flowers and fruit. When climbing the plants are noticeably less green (somewhat yellow) and with thicker and spongy stems. Charlie also commonly likes to advance along the edge of boundaries (see middle pic above). A physical barrier helps prevent Charlie entering, but it will creep along the margin like mice exploring, seeking a point of entry. The tiniest gap will suffice. Glechoma is particularly problematic when it hangs out with others, like a group of terrorists situating themselves among civilians. This mixing is especially a problem when the associate plant is ground hugging. Charlie was infesting my creeping phlox (see bottom pic above) from which it is impossible to completely eradicate. I gave the matter a think before proceeding to battle since the visual contrasts (color and form) in this arrangement made it appealing. My decision, what I hoped would be a solution, was to remove ALL the plants, and some of the soil, and start over. After the removal, I waited a week, applied a preemergent herbicide trying to prevent a subsequent invasion and planted anew a few weeks later. But Charlie likes that location/situation -- has already been there thus likely some residue -- so I suspect it will return. I will be vigilant.
As I mentioned earlier, Charlie is edible, perhaps harvesting is one of the ways to help control its spread and get a free salad component to boot. Assuming, of course, the plants are free from poisons, which includes herbicides. While possible, I will not, nor would I recommend. As for a chemical solution (i.e., spraying your way free, the quick and easy fix most people {the gullible majority} want and that they have deluded themselves into thinking is always available), likely NOT. I have tried an application of a 5% boron solution (~1/4 cup 20 Mule Team Borax / gallon water) with some success. This method requires repeated application and seems to only stunt the plant. I have found that this method works best in fall just before the first frost or killing freeze -- the conditions prompt the plants to translocate compounds from the aerial parts to the subterranean portion. I also describe this approach on page 225 of my Rantings book. However, I have forsaken this more "organic" approach (1) because it is so time-consuming (repeat applications), (2) due to the effectiveness (or should I say ineffectiveness), and (3) for fear the boron would cause long-term damage to my soil as well as the real potential for collateral damage -- to invertebrates (especially ants) and nearby desirable plants. As for the heavy artillery, any herbicide that contains triclopyr is effective, especially in combination with 2-4-D and Dicamba. Proper application is tedious and requires diligence. Spray once and forget about it WILL NOT WORK other than as a spot and temporary victory. Moreover, the associated damage is often considerable. Making matters worse, this thug reproduces readily both sexually and asexually. The seeds are small, brown, pitted, egg-shaped and 2-4 per fruit. Reality is, like with herpes, once infected you will never completely get rid of it, but I keep trying, attempting to at least keep it somewhat in check. Persistence can sometimes be the mark of a good gardener. Since there is no biological control other than reducing preferred habitat, seems it is either chemistry to the rescue or moving to a region (like the desert) inhospitable to Charlie.
Another thing I have learned about Charlie is that while it loves wood chips, like many other annoying bed garden weeds (e.g., violets), it does not like leaf mulch. Mind you, using mulched leaves can be challenging -- especially because it is contrary to what most poeple are accustomed to and leaf mulch is not appropriate for most ground cover taxa. But know this: in many instances leaves are the best mulch option, and Nature's way -- although you should avoid black walnut and ginkgo (a small percent of either is not a problem). I discuss leaf choice further in chapters 38 (Composting), 41 (Allelopathy) and elsewhere in my ranting book. The gold standard for leaves to mulch is maple (available in quantity and quick to decompose) but, like with wine, a good blend is hard to beat -- I favor white oak in the mix and shredding is recommended. As for method, I find that one chopping with my mulching mower before spreading is perfect -- set on high deck with collecting bag attached. YOU SHOULD USE YOUR LEAVES RATHER THAN BAG AND PLACE THEM BY THE CURB. ONE OF MANY THINGS (life & gardening) ABOUT WHICH WE ARE MISGUIDED & IGNORANT!
Creeping Charlie is an attractive but vexatious plant I have gotten to know all too well. Given the challenge it presents, perhaps the more rational approach is resigned tolerance, forbearance. Learning to live together. A truce. It does after all produce beautiful, clustered flowers in spring to mid-summer. The flowers are light blue with a hint of lavender, funnel-shaped, with the exposed portion of the corolla flattened, bilaterally symmetric and spotted (romperlike, see top pic above, and reminiscent of violets). Furthermore, the plants are gynodioecious -- either female or hermaphroditic -- and the flowers are visited by many different pollinators. It is not the worst thing out there, but on days I am trying to corral Charlie it can seem so.
