This intricately branched, heath-like shrublet is well known to
hikers who use the plant to make soft mattresses when sleeping outdoors.
It might be better known to many people as Stoebe plumosa.
Despite enormous garden potential and successful use at Kirstenbosch,
it is not yet commonly cultivated.
first glance, Seriphium plumosum appears to be a sprawling,
much-branched, grey shrub. Looking closer, one notices that the
slender, wiry branches are softly woody and at right angles to the
stem. The short shoots are covered with whitish, woolly, clustered
leaves, which are minute, tufted and pressed to the stem, giving
the plant a granular appearance.
In the wild there are different forms, varying in colour. The
silver-grey form that is grown at Kirstenbosch is usually found
at higher altitudes and has slightly thicker stems.
flowerheads are grouped in small clusters towards the ends of the
main shoots, forming a spike-like inflorescence. Pale brown bracts
surround the purple disc florets and give the spikes a golden appearance.
Flowering is mainly in autumn/winter, from April to June, but also
The genus Stoebe consisted of 34 species occurring mainly
in the Western Cape (25 species) but also in southern tropical Africa,
Madagascar and Reunion. It was recently revised by Koekemoer (2002)
and Stoebe plumosa was combined with some other stoebes as
Seriphium plumosum. S. plumosum is quite common and
has a widespread distribution throughout South Africa.
Derivation of name and historical aspects
The name Seriphium is derived from seriph, a stroke or line
of a letter; plumosum means feathery.
There is speculation whether the common name slangbos is
derived from the fact that the flowerheads look like a snake rearing
its head or from unsuspecting individuals finding a cobra curled
up under it.
The species' light colour, which reflects sunlight, woolly covering
and small leaves, which reduce water loss, are adaptations to survive
long, dry summers. It is an aromatic plant, yielding volatile oil,
which is also a protective measure as the plant is seldom eaten
by stock and then only when the plant is young. This is the very
reason why the form of Seriphium plumosum which was previously
known as Stoebe vulgaris has become such a problem in the
northern parts of the country where it proliferates in disturbed
or overgrazed areas, explaining its common name, the bankrupt bush.
Uses and cultural aspects
The form of Seriphium plumosum which was previously known
as Stoebe plumosa was not used medicinally. However, in the
Western Cape, the form previously known as Stoebe cinerea
is still used as a remedy for heart trouble, whereas another unidentified
Stoebe/Seriphium sp. that smells like valerian, may have
a beneficial effect in epilepsy.
Slangbos provides interesting, long-lasting foliage for
the vase. Dried and fresh material is popular in the floral industry
especially around Christmas time when silver foliage is very sought
after. It also often features at the Chelsea Flower Show where it
is used as a filler in the Kirstenbosch/South African exhibit.
The plant makes very good kindling for fires, so good in fact that
it should not be grown too close to a house in high fire risk areas.
It is also used as nesting material in aviaries, tightly stuffed
into chicken-wire baskets or nesting boxes, and is favoured by zebra
finches. Any outdoor enthusiast will testify that the plant makes
very good bedding material.
Growing Seriphium plumosum
Providing striking colour and contrast in the garden, slangbos
is wonderful as an edging plant, bedding plant or groundcover. Not
only does the foliage provide contrast, the spike-shaped flowers
also contrast with other flowerheads.
Seriphium plumosum is evergreen and fast growing, with a
height and spread of about a metre. Plant in full sun in well-drained
soil or on a slope and keep fairly dry in summer. It looks most
natural when combined with other fynbos, especially proteas and
restios. Where less of a contrast and a more natural look is desired,
use in variegated, grey and yellow planting schemes. For the best
effect plant it in groups and give it space to spread or keep in
shape with a regular light prune.
At Kirstenbosch slangbos is propagated vegetatively. Tip
cuttings are taken in spring, treated with a rooting hormone and
inserted into a 50% bark, 50% polystyrene medium and placed on 24°C
bottom heat under a mist system. Rooting usually takes three weeks.
Cuttings can also be rooted in coarse river sand in cold frames.
Seed is also an option and is sown in autumn.
References and further reading
- Germishuizen, G. 1997. Wild flowers of northern South Africa.
Fernwood Press, Cape Town.
- Goldblatt, P. & Manning, J. 2000. Cape plants. A conspectus
of the Cape flora of South Africa. Strelitzia 9. National
Botanical Institute, Cape Town and Missouri Botanical Garden Press.
- Jackson, W.P.U. 1980. Wildflowers of the fairest Cape.
Howard Timmins, Cape Town.
- Koekemoer, M. 2002. Systematics of the Metalasia group in
the Relhaniinae (Asteraceae-Gnaphalieae). Unpublished Ph.D.
thesis. Rand Afrikaans University, Johannesburg.
- Manning, J. & Goldblatt, P. 1996. West coast. South
African Wild Flower Guide 7. Botanical Society of South Africa,
- Powrie, F. (ed.). 1998. Grow South African plants. National
Botanical Institute, Cape Town.
- Van Rooyen, G. & Steyn, H. 1999. Cederberg-Clanwilliam
& Biedouw Valley. South African Wild Flower Guide 10.
Botanical Society of South Africa, Cape Town.
Kirstenbosch National Botanical Garden
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