Miss Floribunda: Identifying pretty, invasive plants
Dear Miss Floribunda,
Of late you have been raising my consciousness about the dangers of certain invasive volunteer plants and I wonder if I am wrong to tolerate a number of weeds because I think they are pretty. I recognize the golden rod, the purple thistles that bring beautiful gold finches to my garden, the Queen Anne’s Lace and tiny wild asters, none of which seem to me to be a problem. However, I’m not sure about a grass with long stems that look as if they are covered with lots of little pink beads. It dries very well for winter bouquets. The leaves have a flavor a bit like sorrel and the stems actually taste a lot like rhubarb. This plant is very attractive to butterflies but it does spread. Do you know what it is and if it is a menace?
Another interloper I can’t identify is a little three-petaled flower of a wonderful morning-glory blue, very low growing. The stems taste like celery and the leaves a bit more peppery. Bees go for this one. Then there is another plant that at first I mistook for garlic mustard, which I know is a pest. This weed is much more attractive and when I tasted the leaves they didn’t have any garlic taste. Its fuzzy white flowers resemble those of ageratum. It will take over if I don’t thin it out quite a bit. However, because the butterflies and I love it I am hoping you will give it a pass.
Nibbler on Nicholson Street
First of all, I beg you to be careful what you bite into. The plant that resembles ageratum is indeed of the same family (Asteracae) and tribe (Eupatoreae) that ageratum comes from, and some of these are poisonous. The pink-beaded one is from the Polygonaceae family, which is known to cause rashes in sensitive people. This time you nibbled with impunity, unless you are writing from another dimension, but next time you might get a stomach upset or worse. Odor as well as taste can help identify plants. You might crush their leaves in your hand in order to release their fragrance, perhaps wearing gloves for good measure.
I have seen the fuzzy white wild flower (not weed) in my own garden and in adjoining alley ways. It is generally called late-flowering boneset and is a medicinal plant used by Native Americans as a cure for flu–not to set bones. At first I thought it might be the white-mist flowerI admired when visiting my Cousin Kickapoo in Texas, and it is a related eupatoreum, but it blooms earlier and is limited in range to the Southwest. I seriously doubt that anyone would have taken the trouble to rustle it up here. Both are great butterfly favorites not seriously difficult to control.
The pink beaded plant is pink knotweed, aka smartweed. It also has medicinal uses, ranging from use as a foot soak to an attempted cure for cholera. On a recent visit to the Jardin des Plantes in Paris with my friend Mlle. Noisette I was surprised to see it in the “simples” section devoted to useful herbs. A little research revealed it to be native to Europe and invasive here. Like the ranunculus that became the buttercup, it took advantage of the freedom of the New World to escape from cultivated beds to frolic in the wild. Its saving grace is that it is an annual, and because you pick the flowers to dry for winter use before they go to seed, you should be able to keep it under control.
The prostrate plant with the beautiful blue blooms is from the Commelina family, known here as the Asiatic dayflower, and of course it comes from Asia. The Virginia Department of Conservation and Recreation has categorized it as “occasionally invasive.” It is used as a dye in Japan and for medicine in China, supposedly very good for sore throats. I would still be cautious, though, and not make tea from it.
To talk with other plant lovers and to perhaps acquire some new plants, come to the next meeting and autumn plant exchange of the Hyattsville Horticultural Society. It will take place on Saturday, October 18, from 10 AM to noon, at the home of Joe Buriel and Dave Roeder, 3909 Longfellow Street.