Wachendorfia is a small genus of four perennial herbaceous plants in the family Haemodoraceae (order Commelinales), endemic to the fynbos biome of South Africa's Cape Provinces. Plants grow 10–250 cm tall from a distinctive fleshy, rounded to cylindrical underground rootstock that bleeds bright red sap when cut — a feature shared with other members of the bloodroot family.
The leaves are arranged in a fan-like structure and are unusual in being flattened sideways, producing left and right surfaces rather than the conventional upper and lower ones. They are lance- to line-shaped, pleated along their length, and in three of the four species die back after the seeds are shed; only W. thyrsiflora is evergreen. The inflorescence is a panicle of zygomorphic, pale apricot to golden yellow flowers with six spreading tepals. One of the genus's most striking features is enantiostyly: in any given plant the style is consistently deflected either to the left or to the right, with one stamen curving the same way and the remaining two curving in the opposite direction. This left-right dimorphism across plants is thought to promote cross-pollination and boost genetic diversity.
The genus comprises four accepted species. W. thyrsiflora, the largest (to 2 m), is evergreen and restricted to stream banks and seeps. W. paniculata is a highly variable deciduous species tolerating both dry and wetter conditions. W. brachyandra is distinguished by clustered stamens less than half the tepal length. W. multiflora (formerly Babiana multiflora) is a small plant rarely exceeding 25 cm. The genus was formally described by Johannes Burman in 1757 and named in honor of Evert Jacob van Wachendorff, 18th-century professor of botany and chemistry at the University of Utrecht.
Etymology
The genus is named in honor of Evert Jacob van Wachendorff (1703–1758), professor of botany and chemistry at the University of Utrecht in the Netherlands, who later served as rector of that university. The name was established by Johannes Burman in his 1757 monograph of the genus.
Distribution
All four species of Wachendorfia are endemic to the fynbos biome of South Africa's Cape Provinces. W. thyrsiflora and W. brachyandra are restricted to permanently moist habitats such as stream banks and seeps, while W. multiflora and W. paniculata occur in seasonally or persistently dry fynbos.
Ecology
The flowers of Wachendorfia are enantiostylic: across any population, individual plants consistently bear either left-deflected or right-deflected styles, with one stamen curving in the same direction and two opposing. This chiral dimorphism is thought to promote cross-pollination and genetic diversity. All species flower in spring and early summer; W. multiflora blooms in August–September, W. thyrsiflora can extend flowering into summer as it inhabits permanently moist sites and does not suffer summer water stress.
Cultivation
Wachendorfia species are slightly frost-hardy and perform best outdoors in warm, near frost-free climates as ornamental plants. They require moist, well-drained soil in a sunny position; W. thyrsiflora in particular suits bog gardens or pond margins. Propagation is by seed or division.
Taxonomy Notes
The genus was first effectively described by Johannes Burman in 1757. Early pre-Linnaean names (Erythrobulbus by Leonard Plukenet, 1700; Asphodelus latifolius by Johann Philipp Breyne, 1739) are invalid. Pehr Löfling had applied the name Wachendorfia to a genus in Commelinaceae, but his posthumously published work (1758) postdates Burman's 1757 monograph, giving Burman's name priority; Löfling's homonym was replaced by Callisia. A revision by Nick Helme and Hans Peter Linder in 1992 settled the genus at four species. In 2000 John Manning and Peter Goldblatt transferred Babiana multiflora Klatt (1882) to Wachendorfia as W. multiflora, which has nomenclatural priority over the synonym W. parviflora.
