Much treasured as a garden flower, this native perennial is abundant in some of our wooded parks. Here we see a large patch in Bird Park, Mount Lebanon.
Sometimes a white or nearly white form appears; the range of shades is continuous from deeper blue to almost pure white.
For a description of the species, see the Phlox divaricata reference page.
Blue or Woodland Phlox blooming along the Trillium Trail, Fox Chapel, April 22. For a full description, see the Phlox divaricata reference page.
This beautiful plant has appeared here more than once, but here we have some fine deep pink Phlox from the Seldom Seen Greenway, where they were growing next to Saw Mill Run.
We repeat what we have said before about Phlox paniculata:
Pittsburgh is in the native range of Phlox paniculata, but the flower is so popular in gardens, and persists and spreads for so many years after planting, that we always have to suspect any individual plant of being a garden escape. It is often found near old homesites (as it was here in Seldom Seen, where the trail along Saw Mill Run was the main street of a little village until sixty years ago).
Phlox is so much beloved in Pittsburgh that any plant with a vaguely similar inflorescence is likely to be called “Phlox,” Dame’s Rocket (Hesperis matronalis) and Soapwort (Saponaria officinalis) being two notable examples. This, however, is the real thing.
The flowers come in a range of colors from white through pink to purple. In the Pittsburgh area at least, the species shows a remarkable affinity for the edges of old cemeteries, where perhaps it was once a popular planting.
Blue Phlox is certainly one of our most ornamental woodland flowers, and a garden treasure as well. These plants were blooming in early May in Bird Park, Mount Lebanon, where you can find great drifts of Blue Phlox on the wooded hillside overlooking the field.
In the picture at the top of the article, note the occasional four-petaled flower.
Gray describes the genus and the species:
PHLOX L. Calyx somewhat prismatic, or plaited and angled. Corolla with a long tube. Stamens very unequally inserted in the tube of the corolla, included. Capsule ovoid, with sometimes 2 ovules but ripening only a single seed in each cell. — Perennials (except a few southern species), with opposite and sessile perfectly entire leaves, the floral often alternate. Flowers cymose, mostly bracted; the open clusters terminal or crowded in the upper axils. (Phlox, flame, an ancient name of Lychnis, transferred to this North American genus.) Most of our species are cultivated in gardens.
Herbaceous, with flat (broad or narrow) leaves.
Stems, at least the flowering ones, ascending or erect; flowers in corymbed or simple cymes; corolla-lobes obovate or obcordate.
Calyx-teeth long and slender; more or less hairy or glandular-pubescent.
Leafy shoots from the base creeping or decumbent; leaves rather broad.
P. divaricata L. (BLUE PHLOX.) Stems spreading or ascending from a decumbent base, 2-5 dm. high; leaves oblong- or lance-ovate or the lower oblong-lanceolate, 2-6 cm. long, acutish; cyme corymbose-panicled, spreading, loosely flowered; calyx-teeth slender awl-Shaped, longer than the tube; lobes of the pale lilac or bluish corolla obcordate or wedge-obovate and notched at the end, or often entire, equaling or longer than the tube, with rather wide sinuses between them. — Rocky damp woods, w. Que. to Minn., and south w. May, June — A form occurs near Crawfordsville, Ind., with reduced flowers, the narrow entire acuminate corolla-lobes scarcely half as long as the tube.
Pittsburgh is in the native range of Phlox paniculata, but the flower is so popular in gardens, and persists and spreads for so many years after planting, that we always have to suspect any individual plant of being a garden escape. So this one may have been, but if so it made its escape long ago. It was growing well back in a thicket in a wooded area in Scott, where it was blooming in early July.
Phlox is so much beloved in Pittsburgh that any plant with a vaguely similar inflorescence is likely to be called “Phlox,” Dame’s Rocket (Hesperis matronalis) and Soapwort (Saponaria officinalis) being two notable examples. This, however, is the real thing.
The flowers come in a range of colors from white through pink to purple. In the Pittsburgh area at least, the species shows a remarkable affinity for the edges of old cemeteries, where perhaps it was once a popular planting.
Gray describes the genus and the species:
PHLOX L.
Calyx somewhat prismatic, or plaited and angled. Corolla with a long tube. Stamens very unequally inserted in the tube of the corolla, included. Capsule ovoid, with sometimes 2 ovules but ripening only a single seed in each cell. — Perennials (except a few southern species), with opposite and sessile perfectly entire leaves, the floral often alternate. Flowers cymose, mostly bracted ; the open clusters terminal or crowded in the upper axils. (Phlox, flame, an ancient name of Lychnis, transferred to this North American genus.) Most of our species are cultivated in gardens.
§ 1. Herbaceous, with flat (broad or narrow) leaves.
* Stem strictly erect; panicle pyramidal or ellipsoid, many-flowered; peduncles and pedicels very short; corolla-lobes entire.
P paniculàta L. Stem stout, 0.5-1.5 m. high, smooth, or puberulent or villous above; leaves oblong-lanceolate and ovate-lanceolate, pointed, large, tapering or rounded, the upper often heart-shaped at the base; panicle ample, pyramidal-corymbed, calyx smooth or glandular-hispid, the teeth awn-pointed; corolla pink-purple varying to white. (Including P. acuminata Pursh, P. glandulosa Shuttlw., and P. amplifolia Britton.) — Open woods, Pa. to Ill., Kan., and southw.; escaped from cultivation northw. July-Sept. — Highly variable in outline of leaf, pubescence of leaves, stems, calyx, and corolla, hut without concomitant characters.
