Gasteria loedolffiae Van Jaarsv.
Common names: Mzimvubu ox-tongue (Engl.); Mzimvubu-beestong (Afr.)
Gasteria loedolffiae is a aloe-like plant growing as solitary specimens or forming small groups on sheer shale cliffs of the Mzimvubu and Msikaba Rivers in the Pondoland region of the Eastern Cape. Its panicles of dark pink flowers appear in summer. Its dull green narrower leaves and larger flowers distinguish it from Gasteria excelsa which it superficially resembles.
Plants single or dividing to form small groups. They are long-lived perennials. The roots are succulent and about 2.5 mm in diameter.
The leaves are at first ascending, becoming spreading, spear-shaped and in dense rosettes, faintly white-spotted. It is 165–230 mm long, 60–65 mm broad at the base and slightly sickle-shaped. The upper surface is channelled at the base, the lower surface convex and with a distinct eccentric keel. Both surfaces are dull green and smooth. The margin is leathery and with very small serrated teeth and sometimes entire. The leaf tip ends in a short sharp point (mucronate). The juvenile leaves are tongue-shaped and with the same texture as the adult leaves.
The inflorescence consists of a flat-topped panicle up to 1150 mm long and with up to 6 branches, but younger plants bear an unbranched raceme. The inflorescence stalk can be up to 330 mm long. The flowers tips all point in the same direction (secund) and up to 6 flowers open at the same time. The flowers (perianth) are dark pink, pendent, tubular19–27 mm long, curved in the middle and the 6 floral segments fused for their greater length. The floral tips are free and white with a median green stripe. The flower bracts are 6–7 mm long. The flower stalks are also pendent and about 4 mm long. Each flower has 6 stamens, the yellow anthers just protruding at the floral mouth.
Gasteria loedolffiae flowers in the summer months (January to February in the southern hemisphere).
Although Gasteria loedolffiae is confined to the two river systems (see below), it has not been included in the Red List of South African plants (Raimondo et al.) (http:// Redlist.sanbi.org).
Distribution and habitat
This plant is only known from two river systems in the northeastern portion of the Eastern Cape. These are the Mzimvubu River and its tributaries, as well as the upper Msikaba River to the north. The Mzimvubu River is a large river system which drains the southwestern portion of the Drakensberg Mountains. These rivers are botanically not well known due to a lack of accessible roads. The plants grow in crevices of usually inaccessible shale cliffs (various aspects), in full sun or sometimes in shade. The vegetation where G. loedolffiae grows, consists of Eastern Valley Bushveld (Mucina 2006).
Derivation of name and historical aspects
Gasteria loedolffiae honours the Cape Town-based botanical artist, Jeanette Loedolff. Jeanette has illustrated this and all the other species of Gasteria for a forthcoming book on the subject. Gasteria loedolffiae was named in the British Journal, Bradleya in 2014, by the author (Van Jaarsveld 2014). In April 2002, the Mzimvubu River was investigated by the author, uPhakamani Xaba and Adam Harrower, using rubber canoes. This is when Gasteria loedolffiae was found (Van Jaarsveld 2003).
The nectar-rich flowers of Gasteria loedolffiae are regularly visited and pollinated by local sunbirds. The leaves of G. loedolffiae are brittle as with most Gasteria species, and when becoming detached, soon root, forming new plantlets. The plants grows on sheer cliffs where the larger herbivores cannot reach them.
Adjacent to the Mzimvubu River, plants are frequently encountered on the local Pondo people’s roofs. They are grown on the rooftops of the dwellings in the belief that these plants protect the hut from lightning strikes.
The plants are also grown for ornamental purposes in gardens and containers in botanical gardens and elsewhere. The Mzimvubu is a name given by the Xhosa for this river and pertains to the Hippopotamus that were once widespread in this river system.
Growing Gasteria loedolffiae
Gasteria loedolffiae grows well in cultivation and is best grown in bushveld gardens (Van Jaarsveld 2010) in rockeries, embankments, dry stone walls or containers. Plants can be grown in full sun or shade.
In regions where frost occurs, it is best to grow them in a greenhouse under controlled conditions. The plants are slow growing and take at least three to four years to flower, when grown from a young plant. This plant is easily grown from division, seed or leaf cuttings. Sow seed in autumn, spring or summer. Cover the seed with a thin layer of sand and keep moist. Apply a fungicide when necessary. Transplant seedlngs when large enough to handle.
Plants react well with an annual compost dressing. They can also be fed with an organic fertilizer should it be necessary. The plants grow well in a soil mixture designed for succulents, as long as it is well drained.
- Mucina, L. & Rutherford, M.C. 2006. The vegetation of South Africa, Lesotho and Swaziland. Strelitzia 19. South African National Biodiversity Institute, Pretoria.
- Van Jaarsveld, E.J. 1994. Gasterias of South Africa. Fernwood Press, Vlaeberg.
- Van Jaarsveld, E.J. 2003. The Mzimvubu River botanical expedition. Veld & Flora 89 (3): 101–105.
- Van Jaarsveld, E.J. 2010. Water wise gardening. Struik, Cape Town.
Ernst van Jaarsveld
Plant Type: Succulent
SA Distribution: Western Cape
Soil type: Loam
Flowering season: Early Summer
Flower colour: Pink
Aspect: Full Sun, Morning Sun (Semi Shade), Afternoon Sun (Semi Shade)
Gardening skill: Easy