Plectranthus venteri Van Jaarsv. & Hankey
Common names: Sekukuni spurflower (Eng.); sekoekoeniespoorsalie (Afr.)
A relatively new species to horticulture, Plectranthus venteri is a uniquely aromatic, sun-loving, water-wise Plectranthus.
Erect, multistemmed, aromatic shrub, 0.3–0.6 m high and up to 1 m across. The entire shrub is covered in hairs. The leaves have an attractive triangular shape with lobed or dissected margins.
A single terminal raceme, which rarely bears a pair of side branches at the base of the inflorescence, displays deep mauve to violet flowers in late summer to autumn.
The corolla is 8–10 mm long, tubular with a slight bend in the tube. Flattened nutlet seeds are produced and usually dark brown to black. Fast growing once established and long lived.
According to the Red List of South African plants website, checked on 5/04/2018, the conservation status of this plant is Rare. Plectranthus venteri comes from a restricted range and known from less than ten sites. However, the habitat is inaccessible and not threatened.
Distribution and habitat
Endemic to South Africa, with a distribution restricted to the Sekhukhuniland area in the Limpopo Province, usually occurring in shallow, gravelly soil and rocky pockets, amongst norite boulders, in the bushveld complex of heavy metal, igneous rocks. Here it grows in full sun or in the shade of boulders.
Derivation of name and historical aspects
The genus Plectranthus was established in 1788 by a French botanist and magistrate Charles Louis L'Héritier de Brutelle (1746–1800). He centred his description of the new genus on the spur present at the base of the corollas of the specimens he had available of Plectranthus fruticosus and P. punctatus. Plectron meaning ‘spur’ and anthos, ‘flower’. Unfortunately, unbeknownst to him, most Plectranthus do not have a spur on their corolla, however, once officially described and published, the name Plectranthus was accepted and used.
P. venteri was named by E. van Jaarsveld and A. Hankey in 1997, after a former South African botanist and ecologist Fanie Venter, who first collected P. venteri on norite koppies in Sekukuniland, in the Limpopo Province. P. venteri is very distinct from other species of Plectranthus and it is unlikely to be confused with any others. Characteristic features are its uniquely lobed leaves, which have a unique, distinct pleasant aroma.
Plectranthus are primarily pollinated by insects and many beneficial insects, such as bees and butterflies, are attracted to the flowers. However, a myriad of insects are pollinators to Plectranthus, depending on the length of their tubular flowers.
The jutting teeth of the persistent calyx of the seed are thought to aid in seed dispersal.
The Sekukuni spurflower will make an attractive ornamental shrublet in bushveld gardens and rockeries or container plantings. It does well in most parts of South Africa, including in winter rainfall areas where it receives sufficient drainage. It tolerates mild frost.
Plectranthus venteri is known as a good insect deterrent. The Plectranthus family is renowned for the number of plants with useful aromatic chemicals. Plectranthus have glandular hairs containing phenolic compounds that deter foraging insects. The glandular hairs secrete etheric oils that release a strong aroma when touched.
Growing Plectranthus venteri
Plectranthus species are generally easy to propagate and will root from tip or stem cuttings, in a warm environment and can be propagated throughout the year. Propagate Plectranthus venteri cuttings by using a basic propagation media, in a glass of water or even just placing cuttings directly into the garden area you wish them to grow.
Sow seeds in a well-drained loam mix, in spring. Seeds should readily germinate within 3 weeks. Transplant seedlings as soon as they are easy to handle. A growth media of well-drained sandy loam or compost rich soil, produces lush vigorous plants.
Plants can be pruned to shape after flowering, if required, however they retain a good natural habit.
Plants are best grown in areas of light-shade with good light, or in full sun, which is uncommon for plectranthus.
Species of Plectranthus do get pests and diseases, such as nematodes, caterpillars, aphids, white fly, scale, red spider mite and snails. However, in general Plectranthus species are quite hardy and rarely any trouble to a gardener.
- Rice, L.J., Brits, G.J., Potgieter, C.J. & Van Staden, J. 2011. Plectranthus: a plant for the future? South African Journal of Botany. 77(4): 947–959.
- Van Jaarsveld, E. 2006. The southern African Plectranthus and the art of turning shade to glade. Fernwood Press, Vlaeberg, Cape Town.
Kirstenbosch National Botanical Garden
Plant Type: Shrub
SA Distribution: Limpopo
Soil type: Sandy, Loam
Flowering season: Late Summer, Autumn
PH: Acid, Neutral
Flower colour: Purple, Mauve/Lilac
Aspect: Full Sun, Morning Sun (Semi Shade), Afternoon Sun (Semi Shade)
Gardening skill: Easy