In addition to the weeds (see previous post), there are quite a few species of lamiaceous wildflowers found in the Maryland piedmont. Bloom times given below are based on my observations over the past few years.

Clinopodium vulgare
(formerly Satureja vulgaris) 
wild basil
Wild basil grows in much of Maryland, but I’ve never seen it here; this specimen was photographed in central New York. It’s a circumboreal species; in the US it’s found in the northeast, midwest, Four Corners, and Pacific northwest. This is not the same species as culinary basil (Ocimum basilicum). It grows to about a foot and a half tall in dry soils in sunny areas and open woodlands. Flowers are borne in cymes in the upper leaf axils.

Collinsonia canadensis
horse mint, richweed, stone root
This species is found in most of Maryland (but only parts of the coastal plain). It’s native to eastern North America, and is endangered in Wisconsin. It’s a fairly large plant, growing to four feel tall with a three foot spread in sandy and/or loamy soils in woodlands.  I’ve found two stands of richweed along the Cabin John trail; both sites are moist to wet and rather shady. Small flowers are borne on large terminal panicles in mid to late summer.

Cunila origanoides
common dittany, American or Maryland dittany, frost mint, stone mint, sweet horse mint, fairy skirts
Dittany is found from eastern Texas to southern New York late. There are records for it in most of Maryland, but I’ve only seen it once, in the woods at Serpentine Barrens Conservation Park in central Montgomery County. Dittany is a late-summer blooming perennial, growing to about two feet tall, with flowers borne in cymes or panicles in the upper leaf axils.

Lycopus uniflorus
northern bugleweed, northern water horehound
Lycopus virginicus
Virginia bugleweed, Virginia water horehound
Two very similar looking species, differentiated by leaf shapes, presence/absence of hairs on stems, shape of calyx teeth, and other little details. Both are moisture-loving perennials growing to about three feet tall, with tiny flowers in cymes in the upper leaf axils. The late-summer blooming flowers are not at all showy.

Mentha arvensis
wild mint, field mint
This species is not one of the culinary mints, but like them it can be an aggressive grower. It’s a perennial that grows to two feel tall in moist soils with some sun, blooming in mid to late summer. Flowers are borne in cymes in the upper leaf axils. A circumboreal species, it’s found in most of the US, except in some southern states, and is listed as weedy by some authorities.

Monarda clinopodia
basil balm, white bergamot, basil bee balm
Basil balm is on the Maryland RTE watchlist (S3); it’s found only in the piedmont and a few areas to the west. There’s one vigorous stand along the Potomac that I visit every year to see the bees carousing in the blossoms, from about mid June to mid July; like other Monarda species it’s a great attractor of pollinators. Its greater range includes most of the Appalachian states and parts of the mid-Atlantic, with some occurrences in southern New England and the midwest. It’s endangered in New Jersey and New York. The plants stand to about three feet tall, growing in moist soils in open woodlands. The flowers are borne in terminal cymes.

Monarda fistulosa
wild bergamot, bee balm
Except for California, Florida, and Alaska, and Rhode Island where it’s listed as historical, every state in the continental US has one of the seven varieties of M. fistulosa. In Maryland it’s found throughout the piedmont. Like many mint family species, this one can grow aggressively, spreading far and fast in ideal conditions. If you can keep it under control it makes a lovely garden plant that attracts several species of bees and butterflies. It can grow in sun to part shade, in many different types of soils, though it prefers drier ones. In humid conditions (eg, if overcrowded) it can develop mildew. Bee balm is a many-branched perennial growing to about 4 feet tall. The flowers are borne in terminal cymes. Despite the common name, it isn’t related to the bergamot that flavors Earl Grey tea (that’s Citrus bergamia, in the Rutaceae).

next time: more lamiaceous wildflowers