Bugles (Ajuga reptans). This is a popular groundcover at garden centers, usually in varieties with bronze or variegated leaves. The original green-leaved version is thoroughly naturalized here; it persists in old plantings for decades, but it also pops up on its own, especially at the edge of an open woodland. The common form is blue; there is also a much rarer lavender form.
Wood Sage (Teucrium canadense). A stately member of the mint family, whose straight and tall spikes would not be out of place in a formal perennial garden. It blooms in the middle of the summer with tall spikes of pale lavender or pinkish flowers held above the leaves. The leaves are narrowly oval, with shallow teeth
Purple Giant Hyssop (Agastache scrophulariifolia). Not a terribly common plant around here; this patch was growing in a clearing in Scott, where it was blooming in late August. The flowers are irresistibly attractive to butterflies. The leaves have a noticeable anise scent, not as strong as but very much like the scent of its more commonly cultivated cousin, Anise Hyssop (A. foeniculum). The two species are very similar; the most obvious difference is in the length of the flower spikes, which in A foeniculum are usually not much longer than your thumb, but in this species can easily exceed your longest finger.
Catnip (Nepeta cataria). This is probably your cat’s favorite herb, but it seems to have almost the same intensely euphoric effect on little white butterflies, to judge by the swirling masses of them that were visiting this plant. It was blooming in late July at the edge of an overgrown gravel drive in Scott Township. A tisane can be made from the leaves, but your cat will probably drink it before you get a chance at it.
Ground Ivy (Glechoma hederacea). Ground Ivy, Creeping Charlie, or Gill-Over-the-Ground is a foreign invader, and for grass purists it’s a hated broadleaf weed. It is, however, easy to get along with. It smells minty fresh when you mow it, and it produces these stunningly beautiful flowers in the spring.
Heal-All (Prunella vulgaris). Heal-All, or Self-Heal, is everywhere; it tolerates a good deal of mowing, and seems to be indifferent to sun or shade, so it can establish itself in urban lawns as easily as at the edge of the woods. The color of the flowers is variable from deep purple to (rarely) pure white, including bicolors. The blooming season is very long, beginning in late spring and lasting into the fall.
Obedient Plant (Physostegia virginiana). Also known as False Dragonhead, referring to its resemblance to a snapdragon. The name “Obedient Plant” describes a property that fascinates children, and any adults who are not too jaded to admit to being fascinated. If you push one of the individual flowers to the left or right, it will stay in that position. You can arrange all the flowers artistically on the stem, and they will stay right where you put them. You might almost think the plant had been specially bred by lazy florists.
Motherwort (Leonurus cardiaca). Easily distinguished from anything similar by the foamy appearance of the flowers, which have puffy tufts of hair on their upper lips. “Motherwort” is so named because it was used by herbalists for what have traditionally been called “female difficulties.” It blooms in the early and middle summer, and especially likes a shady spot in thick growth at the edge of the woods.
Purple Archangel (Lamium purpureum). Also known as Purple Dead-Nettle. This beautiful little flower grows everywhere along the street in the city. It starts blooming quite early, sometimes before winter is over, and by the end of April is in full flower. The whole plant is tiny, and the flowers would be inconspicuous, except that the upper leaves are various shades of purple or dark pink, setting off the pale pink flowers beautifully.
Yellow Archangel (Lamium galeobdolon). A European plant often cultivated here as a ground cover, but increasingly escaping into the wild. It is also commonly placed in the genus Lamiastrum, or “False Lamium.” So it is classified in the USDA PLANTS database, which records it as found in the wild in Pennsylvania. Both cultivated varieties and escapes often have variegated leaves.
Lamb’s Ears (Stachys byzantina). The fleshy soft, hairy leaves delight children and any adult not too far gone to take pleasure in simple tactile sensations. The purple flowers make a gorgeous contrast to the whitish hairs of the leaves and stems, but appear only for a relatively short time. This is a garden favorite that seeds itself liberally: once you plant Lamb’s Ears, you have them forever, and they pop up in unexpected places.
Wild Bergamot (Monarda fistulosa). A native plant so popular in gardens that it may as easily be a garden escape as a properly wild plant. It can colonize recently disturbed ground very quickly; after a few years, it seems to give way to slower but more determined neighbors.
Bee-Balm (Monarda didyma). Monarda is a fascinating example of parallel evolution: it makes a display by clustering small ray-like flowers together in one head so closely that the head is often taken for a single flower. In other words, it adopts the method of the Compositae. This particular species is bright red, which is a very attractive color to hummingbirds. It is otherwise very similar to Wild Bergamot (M. fistulosa), which is rather more common around here. This is a native perennial, but much used as an ornamental planting, so that it is difficult to distinguish truly wild populations from garden escapes.
Lemon Balm (Melissa officinaliis). A delightful lemon-flavored mint often planted in herb gardens, from which it immediately begins plotting its escape. The lemon scent (it makes a good herbal tea) and fuzzy stem and leaves are characteristic. Cream-colored buds open into typical white mint flowers in rows of bracts, and bees love them; in fact, the generic name means “bee” in Greek.
Wild Basil (Satureja vulgaris). A hairy and aromatic little mint that likes open woods, and is not above popping up in a shaded lawn, as this one did near Normalville. It’s a close relative of Summer and Winter Savory. The flowers are a delightfully pure shade of pink, hard to reproduce exactly in a photograph.
Bugleweed (Lycopus virginicus). Bugleweed is common at the edges of ponds, often dangling over the water. The leaves often have red veins, and the younger leaves may be red-tinted, especially on the bottom. The little white or pinkish flowers are in tight whorls in the leaf axils.
Spearmint (Mentha spicata). You could look at spearmint as an invasive weed, but it gives us so much in return for the space it takes that it’s a hard weed to resent. Spearmint spreads mainly by runners, forming large, dense patches. Its scent and flavor are recognizable at once. It blooms with pleasant spikes of little white flowers in terminal spikes; if you look at the flowers closely, you will notice pink lines, especially on upper lip
Peppermint (Mentha × piperita). If nothing else, the scent and flavor of the leaves are enough to identify the plant. It shows a strong preference for damp locations, although it will grow almost anywhere you plant it. It seldom produces viable seed, but it nevertheless makes a nuisance of itself in some parts of the country. Around here it is only an occasional tasty volunteer.
Apple Mint (Mentha suaveolens). A strong and flavorful mint, similar in scent and taste to Spearmint (M. spicata). The flower spikes are the most distinguishing feature: flowers bloom in dense cylindrical spikes, like green fingers, rather than the looser interrupted spikes of Spearmint. Apple Mint grows in sunny waste places
Horse Balm (Collinsonia canadensis). A big, sloppy mint that likes to grow in the deep woods, with huge leaves (by mint-family standards) and panicles of bizarre yellowish flowers with long projecting stamens. The flowers look like little dragons, and well repay a close look, perhaps with a glass. Only a few of the flowers are open at any one time; the rest are either still in bud or shriveling on the stem, adding to the general appearance of slovenliness. The scent is like cheap artificial lemon perfume.