purpletop vervain
(Verbena incompta P. W. Michael)

Overview

Appearance

Verbena incompta, Brazilian vervain, is a slender, rapidly growing, erect, clump forming perennial herb. The 3-6 ft. (0.9-1.8 m) tall stems are rough and square. Upright branches attachment to main stem is opposite. V. incompta may survive as an annual in colder climates as it readily self-seeds.

Foliage

Leaves of V. incompta are dark green. Most of the leaves are in a basal rosette. The stem leaves are opposite and attach directly to the stem with the leaf base tapering. Leaves are obovate to elliptic to lanceolate, ranging from 3-5 in. (7.6-12.7 cm) long with coarsely serrate margins.

Flowers

V. incompta has small lavender to purple flowers. Each flower has five petals and is borne in compact slender terminal fascicles within hairy sepals and bracts. V. incompta blooms all summer until the first frost.

Fruit

V. incompta fruits are tiny nutlets within the persistent calyx and bracts. Four seeds are produced for each flower.

Ecological Threat

V. incompta is native to South America. It is drought and heat tolerant and is very common along roadsides, new forest plantations, forest edges, right-of-ways and other disturbed areas. Verbena incompta is very similar to V. bonariensis and V. montevidensis. All are invasive species.

Selected Images

Maps

Invasive Listing Sources

• Georgia Exotic Pest Plant Council - Category 4
• Nonnative Invasive Species in Southern Forest and Grassland Ecosystems

References