Wachendorfia thyrsiflora with its large golden flower spikes
is very striking when in flower, and is a must for the marshy garden.
It is a tall evergreen geophyte (perennial plant with underground
buds). The rootstock is a branched, fleshy rhizome with clusters
of thin adventitious roots at the nodes. The rhizome is a distinctive
red colour, containing a red fluid rich in arylphenalenone pigments.
The leaves are firm, hairless, entire and broadly sword shaped,
with very distinctive longitudinally pleated leaf blades. The inflorescence
is a dense cylindrical panicle of bright golden-yellow flowers on
a tall sturdy stalk. Flowers are produced from spring until mid-summer
(September - December). The leaves are from 0.6 to 1 m tall and
the flower stalks can reach up to 2.5 m in height.
pollinator is unknown and its pollination biology is a bit of an
evolutionary puzzle. The flowers produce a generous amount of nectar
that is easily stolen with the thief not having to get anywhere
near the pollen or stigmas in order to get at the nectar, so there
is no apparent benefit to the plant. Furthermore, the stigma and
anthers are too far apart for most insects, including the honey
bee, to touch when visiting for nectar, and this rules them out
as pollinators. The carpenter bee is a possible pollinator as it
is large enough, or tabanid flies whose wings do touch the anthers,
or any number of beetles that feed on the pollen, clambering over
the flowers to get at the pollen and touching the stigmas in the
process. To add to the puzzle, Wachendorfia has a peculiar form
of floral enantiomorphy i.e. they have left- and right-handed flowers
that are mirror images of each other. Within a population there
are flowerheads with flowers whose stigmas are bent sharply to the
left and another has them bent to the right. Also, one of the stamens
is bent in the direction opposite to the stigma. Enantiomorphy was
thought to promote outcrossing but in Dilatris, also a southern
African member of Haemodoraceae, there are left- and right-handed
flowers on one flowerhead, and the function of this is not understood.
In any event, someone or something does effect pollination and the
resultant fruit is a 3-locular capsule containing three 5 x 3 x
1 mm semi-circular black seeds. They are hard but light in weight
and are densely covered in short coarse hairs which give the seeds
a fuzzy outline. They also float on water, and given the riverine
habitat of the plant, this is probably an adaptation for water dispersal.
Wachendorfia thyrsiflora occurs in the Western Cape and
Eastern Cape, from the Olifants River Valley between Clanwilliam
and Citrusdal, south to the Cape Peninsula, inland as far as the
Franschhoek Mountains and along the south coast as far east as Humansdorp,
where it grows only in permanent marshes, seepages and streams from
5 to 1200 m above sea level.
Haemodoraceae, or bloodwort family, gets its rather alarming name
from the red cell-sap found in the roots which colours the rootstock
red (haima is Greek for blood and dôran means
gift; wort is old English for a plant; Haemodorum
is the Australian genus on which this family is based). It consists
of 13 genera found in Australia, southern Africa and tropical America,
the Australian representative most familiar to gardeners being Anigozanthos,
the kangaroo's paw.
The genus Wachendorfia is endemic to southern Africa and
occurs only in the Western Cape and Eastern Cape. It is a small
genus of four species: Wachendorfia brachyandra, Wachendorfia
multiflora (= W. parviflora) a very variable species,
Wachendorfia paniculata (including Wachendorfia graminifolia
now sunk into this species), and Wachendorfia thyrsiflora.
All but Wachendorfia thyrsiflora which is evergreen, are
winter-growing - summer-dormant. The genus is named in commemoration
of E.J. von Wachendorff, the 18th century professor of botany and
chemistry at Utrecht. The specific name thyrsiflora means
that it has flowers in a thyrse. A thyrse is an inflorescence with
a racemose primary axis and cymose lateral axes i.e. the main branch
is ever growing producing new flowers all the time with the youngest
at the top, and it has side branches which end in a terminal flower
with any successive flowers behind it. In strict terms, this does
not apply to Wachendorfia thyrsiflora, as its inflorescence
is not a thyrse but a panicle, which is an inflorescence with a
racemose main axis and racemose lateral axes. I prefer a more romantic
classical derivation from the Latin thyrsus from the Greek
thursos which is a rod or wand tipped with a pine cone, symbolic
of Bacchus/Dionysus, which, gods of wine aside, is perfectly descriptive
of the overall appearance of the inflorescence. The common names
of bloodroot and rooikanol (red-rootstock), like the family name,
refer to the red colour of the roots and rhizomes.
The rhizomes can be used to make a reddish brown dye.
Growing Wachendorfia thyrsiflora
Wachendorfia thyrsiflora is an easy plant to grow and is
ideally suited to marshy or swampy conditions in full sun or semi-shade,
but will also grow in soil that is not waterlogged provided it gets
ample water particularly during winter and spring. A generous mulch
of compost is also very beneficial. It is evergreen if it is given
water all year round, but if given total summer drought it may die
down and go dormant, but it is best not to let it dry out during
summer. Wachendorfia thyrsiflora is invaluable in difficult
permanently wet areas, is an attractive addition to the water garden
where it can be planted at the waters edge or where the water overflows,
and it makes an excellent backdrop to the herbaceous border. It
looks good mixed with Dietes bicolor, the yellow wild iris,
and provides an interesting colour combination when mixed with the
blue flower spikes of Aristea major. In a water garden or
permanently wet area, it can be used with a variety of other plants
also suited to this environment, like: Elegia capensis, Cyathea
dregei (tree fern), Zantedeschia aethiopica (arum lily),
Watsonia meriana, Cyperus papyrus (papyrus) etc. It multiplies
rapidly and can be left undisturbed for several years without flowering
being adversely affected. Wachendorfia thyrsiflora is not
hardy to severe frost, but should be able to survive outdoors in
USDA Zone 10 (-1oC / 30oF minimum), possibly even Zone 9 (-7oC /
20oF minimum) if it is given a protected spot. It is not subject
to any serious pests or diseases.
Propagation of Wachendorfia thyrsiflora is by seed and division.
Seed is sown in autumn, in deep (minimum 10 cm) trays in any good
seedling mix and kept permanently moist. Seedlings will be ready
for transplanting at the beginning of their third season, when they
can be potted into individual pots/bags or planted into the garden.
Flowering can be expected from their fourth season.
Wachendorfia thyrsiflora multiplies rapidly, new rhizomes are produced
annually and it also has the ability to send out stolon-like outgrowths
from the main rhizome, sometimes extending sideways for up to several
metres, which are able to form new plants at the tip. Clumps are
best divided after the flowering period in early summer and replanted
- Helme, N.A., and Linder, H.P., Morphology, evolution and taxonomy
of Wachendorfia (Haemodoraceae), Bothalia 22,1: 59-75 (1992)
- Duncan, Graham, Personal communication.
- Smith, C.A., 1699, Common Names of South African Plants, Dept.
of Agricultural Technical Services, Botanical Survey Memoir No
35, Government Printer.
- Jackson, W.P.U., 1990, Origins and Meanings of Names of South
African Plant Genera, U.C.T. Printing Dept., Cape Town.
- Leistner, O.A. (ed.), 2000, Seed plants of southern Africa:
families and genera, Strelitzia 10., National Botanical Institute,
- Du Plessis, N., & Duncan, G., 1989, Bulbous Plants of Southern
Africa, A guide to their Cultivation and Propagation, Tafelberg,
- Goldblatt, P. & Manning, J., 2000, Cape Plants, A Conspectus
of the Cape Flora of South Africa, National Botanical Institute,
Pretoria & Missouri Botanical Garden Press, Missouri
Author: Alice Notten
Kirstenbosch national Botanical Garden