Oscularia piquetbergensis, just like O. deltoides, is another easy-to-grow succulent groundcover for low-maintenance and water-wise gardens.
Oscularia piquetbergensis is a trailing, perennial shrublet. The stems are succulent and reddish. The sickle-shaped and grey-green leaves have characteristically club-shaped tips. All the observed leaf margins so far are toothless, although the literature does report inconspicuous teeth on rare occasions.
The mildly scented flowers are produced in spring (September-October) and are mainly pink, although white forms also occur. Flowers open in the afternoons. Stamens, being mainly white below and above, are collected into a cone in the centre of the flower. Five separate nectary glands are present.
Fruits: hygrochastic capsules (repeatedly open when wet and close when dry), closing bodies absent, exit of locules blocked by bunches of funicular hairs. Seeds: ovoid, brown.
Oscularia piquetbergensis is not regarded as threatened in its native habitat.
Distribution and habitat
Oscularia piquetbergensis, as the name suggests, is confined to the Piquetberg as well as the mountain range west of Kapteinskloof. It is associated with sandstone rocks, at altitudes above 500 m. Piquetberg is interesting in that three major types of sandstone occur there; O. piquetbergensis is most abundant on what is termed Peninsula Sandstone, and less so on the Piekenierskloof Sandstone.
Derivation of name and historical aspects
Osculum means small mouth in Latin. Oscularia therefore means a group of small mouths and refers to the toothed leaves of O. deltoides. The majority of the 22 species of Oscularia currently recognised in the Plants of Southern Africa online checklist (POSA), however, possess toothless leaves.
The genus is confined to the winter rainfall areas of the Western Cape and can be said to prefer sandstone outcrops, although a number of species also occur on granite.
Oscularia piquetbergensis, like most of its counterparts, almost invariably occurs alone in rocky habitats. This could indicate an intolerance to competition by other plants or could also be an escape mechanism in the frequent fires in the fynbos.
Uses and cultural aspects
Oscularia piquetbergensis is hardly used in horticulture.
Growing Oscularia piquetbergensis
Plants are easily cultivated from cuttings and are well suited to sunny rockeries and steep embankments or as an accent plant in pots. Cuttings are best rooted when planted in sand, but can also be planted directly in the required beds. Seeds should be sown during autumn.
Reference and further reading
- Smith, G.F., Chesselet, P., Van Jaarsveld, E.J., Hartmann, H.E.K., Hammer, S., Van Wyk, B-E., Burgoyne, P.M., Klak, C. & Kurzweil, H. 1998. Mesembs of the world. Briza Publications, Pretoria.
Matt H. Buys
To find out if SANBI has seed of this or other SA species, please email our seedroom