1911 Encyclopædia Britannica/Verbena

VERBENA. The genus Verbena (vervain) in botany gives its name to the natural order (Verbenaceae) of which it is a member. The species are herbaceous or somewhat shrubby, erect or procumbent, with opposite or whorled leaves, generally deeply cut. The sessile flowers are aggregated into close spikes. Each flower has a tubular, ribbed calyx, a more or less irregular tubular two-lipped corolla, with four (didynamous) stamens springing from the interior of the corolla-tube. The anthers are two-celled, with or without a gland-like appendage at the apex. The ovary is entire or four-lobed, and always four-celled, with a single ovule in each cell; the style is unequally two-lobed at the apex. The fruit consists of four hard nutlets within the persistent calyx. There are about eighty species known, mostly natives of tropical and subtropical America, a very few species occurring also in the Old World. The vervein, or vervain, V. officinalis, native of central and north Asia, Europe and North Africa, and common on dry waste ground in the south of England (rarer in the north), was the object of much superstitious veneration on the part of our pagan ancestors, who attributed marvellous properties to it, provided it were gathered in a particular manner and with much complex ceremonial. The plant is now but lightly esteemed, and its medicinal virtues are wholly discredited. The garden verbenas are derivatives from various South American species, such as V. teucrioides, a native of southern Brazil, and V. chamaedrifolia from Argentina and southern Brazil. The range of colours extends from pure white to rose-coloured, carmine, violet and purple. Striped forms also are cultivated. The lemon-scented verbena of gardens, so much valued for the fragrance of its leaves, was once referred to this genus under the name V. triphylla, subsequently called Aloysia, but is now referred to the genus Lippia as L. citriodora; it differs from Verbena in having two, not four, nutlets in the fruit.

The garden verbenas, although somewhat misprized for some years, have once more become popular as bedding plants, and also for pot culture. They are easily raised from seeds sown in heat in February or March, but choice varieties, like Miss Willmott and others, can only be kept true when raised from cuttings. These are best secured from old plants cut down in the autumn and started into growth in gentle heat and moisture the following spring. They root readily in a compost of sandy loam and leaf soil. Besides the garden varieties, V. venosa, a Brazilian species with bluish-violet flowers, is a popular plant for massing in beds during the summer months.