Pentanisia prunelloides (Klotzsch ex Eckl. & Zeyh.) Walp.
Common names: wild verbena, broad-leaved Pentanisia (Eng.); sooibrandbossie (Afr.); icimamlilo (Zulu)
This beautiful blue grassland flower, which attracts butterflies, shows great potential as a garden plant. Widespread in southern Africa, and used extensively in traditional medicine, this attractive small bush grows easily from cuttings.
This plant is an erect perennial herb of about 600 mm, with stout hairy stems, sprouting from a woody rootstock. The leaves, which have no petioles (leaf stalks), are very variable, but are usually ovate with wavy margins. The tubular blue or lilac flowers are in dense heads at the ends of the stems. Flowering occurs in early summer, from August to January. The plants are long-lived and are dormant in the winter months.
There are two subspecies: P. prunelloides subsp.prunelloides, which has erect stems; and P. prunelloides subsp.latifolia which has prostrate (creeping) stems and rounder leaves.
The species is not threatened.
Distribution and habitat
It is widespread in grassland throughout southern Africa, from Eastern Cape to Tanzania, at altitudes from sea level up to 1 980 m. It grows in well-drained soils in full sunlight and tolerates frost.
Derivation of name and historical aspects
P. prunelloides is a member of the gardenia family (Rubiaceae). There are about 15 species belonging to the genus Pentanisia, three of which occur in southern Africa. This group is closely related to the well-known garden plant, Pentas lanceolata, which comes from central Africa. The name is derived from the Greek penta meaning five, anisos which means unequal, referring to the calyx lobes, and prunelloides means resembling the genus Prunella (Lamiaceae) from the Latin prunus meaning purple.
Butterflies and moths use their long tongues to reach the nectar in the bottom of the tubular flower, and in the process carry pollen from one flower to another. One of the first species to flower after veld fires, Pentanisia has a large root which allows it to survive fires and dry winter months.
The Afrikaans common name sooibrandbossie means 'heartburn shrublet' and, in fact, it appears to be a cure-all! The tuberous roots and the leaves of this species are used extensively in traditional medicine to treat a wide range of ailments, although nothing seems to be known about the chemical compounds of the plant. Root decoctions are taken orally or as enemas and also applied externally for burns, swellings, rheumatism, heartburn, vomiting, fever, toothache, tuberculosis, snakebite and haemorrhoids. It is taken by pregnant women to ensure an easy childbirth and leaf poultices are applied for a retained placenta. The Zulu name means 'that which puts out the fire'.
Growing Pentanisia prunelloides
Pentanisia prunelloides is ideal for a grassland bed consisting of grasses mixed with other species such as Berkheya and Vernonia. It can also be used in a border where its compact shape is attractive. However it dislikes root disturbance and usually dies back in winter. This species does not transplant well from the wild as it is difficult to remove the rootstock intact and rot sets in. However, the plant can be propagated by cuttings taken in early summer, which root readily in a well-drained medium such as coarse pine bark. It can also be grown from seed.
- FABIAN, A. & GERMISHUISEN, G. 1997. Wildflowers of northern South Africa. Fernwood Press, Vlaeberg, Cape Town.
- POOLEY, E. 1998. A field guide to wild flowers of KwaZulu-Natal and the eastern region. Natal Flora Publications Trust, Durban.
- VAN WYK, B-E., VAN OUDTSHOORN, B. & GERICKE, N. 2000. Medicinal plants of South Africa. Briza Publications, Pretoria.
KwaZulu-Natal National Botanical Garden
Plant Type: Perennial
SA Distribution: Eastern Cape, KwaZulu-Natal
Soil type: Loam
Flowering season: Early Summer
Flower colour: Blue, Mauve/Lilac
Aspect: Full Sun, Morning Sun (Semi Shade), Afternoon Sun (Semi Shade)
Gardening skill: Average