Slender Vervain (Verbena halei) was, until a few years ago, considered the same as the European vervain (Verbena officinalis), but it is now recognized as a different plant. Misty-looking purple patches on the roadside ahead usually turn out to be masses of the slender vervain. It is a perennial which takes on renewed blooming activity from early spring until fall, but usually only scattered plants bloom after June. It is very abundant in this state and other Southern States.
The flowers are small and scattered along the slender branches at the top of the stem. The upper leaves are narrow, those of the mid-stem divided; and the lower are broad and irregularly toothed.
Large-Flowered Vervain (Verbena plicata) shows some variation in color from white to lavender, the flowers commonly being a bluish-lavender. The flowers are about half an inch broad and grow in long showy spikes. The plants are perennial, and numerous stems form erect clumps 1-2 ft. high. It is especially handsome southwest of San Antonio and ranges into Mexico. It blooms from February to May.
PLAINS VERBENA
Wild or Plains Verbena (Verbena bipinnatifida) is sometimes called sweet William, a name which properly belongs to the blue woodland phlox (Phlox divaricata) or to the clove pink. There is only a faint fragrance to the wild verbena.
Along highways and in the fields the wild verbena blooms in great profusion from spring until the plants are killed by a severe freeze. The flower stalks often grow quite long and are topped by a flat cluster of flowers around the new buds. The old calyx tubes surrounding the small nutlets remain on the stalk for many weeks. Children delight in pulling off the purple tubular corollas so that they can suck the abundant nectar from the tube and then string them together for a necklace, which they make by inserting the base of one tube into the throat of the adjoining corolla.
The wild verbena is a perennial plant with many prostrate branches. The leaves are thick, rough, and divided into narrow segments. It is one of the most familiar plants of the South Plains region, ranging from Missouri and Arizona to Northern Mexico. It is seldom used in gardens, but it is one of the plants used by the highway department for roadside planting. Where it has been used in gardens for low border mass effects, it has been a delight throughout the warm months with its showy, profuse blooms.
“Verbena” is the Latin name for a sacred plant. There are nearly one hundred species of verbenas, one of which is European and the others American. About twenty-five of these are found in Texas, part of them belonging to the vervain group. The plains verbena and the slender vervain are the ones most widely distributed. Among other very lovely verbenas found in the state are Wright’s verbena in West Texas and Lambert’s verbena in East Texas. A South American verbena (Verbena venosa), with brilliant purple flowers, has escaped cultivation in Southeast Texas.
Wright’s Verbena (Verbena wrightii) is quite similar to the plains verbena but has larger flowers of a reddish-purple color. The plants are larger, and the foliage is coarser.