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©Protea Atlas
The genus Serruria is one of the genera of the protea family,
and is found only in the Cape Floral Kingdom.
Name
Serruria was named in honour of J. Serrurier, a professor
of botany at the University of Utrecht in the early eighteenth century.
The specific name cyanoides refers to the resemblance of
its inflorescence to that of Cyanea, a lobeliad from Hawaii.
Distribution
The genus is mainly found in the winter rainfall region, only
Serruria fasciflora extends eastwards to the Langeberg Mountains.
Serruria is the largest of a group of four closely related
genera, Paranomus, Spatalla and Sorocephalus. The
genus has about 50 species and is in fact one of the largest of
the African genera of Proteaceae. S. cyanoides was once common
on the Cape Flats but has disappeared in this area due to urbanization
and the invasion of alien species. The common name derives from
the area in which it originally existed, Wynberg. The remaining
population now survives above the coastal town of Fish Hoek and
at Karbonkelberg in Hout Bay. The plant is listed as Vulnerable
in the Red Data Book.
Description
Serruria cyanoides is a small, densely branched, multi-stemmed,
resprouting shrublet, reaching a height of 400 mm. The dissected
leaves, which are typical of this species, point upwards towards
the flowerhead and are hairless when mature. The plant produces
a solitary, sweetly-scented, pink flowerhead, and flowers from mid-winter
until late spring (July to October). The seeds are released within
two months of flowering.
Natural Habitat and ecology
Herbarium labels indicate that this species occurred at altitudes
of 30 to 550 m on hill slopes and on flats. Collection sites on
record are dunes at the lowest altitudes and sandy southeast slopes
of mountains at the highest altitudes. Serruria cyanoides
now grows in acidic sandy soils at altitudes up to 150 m in isolated
populations of a few hundred plants. The Wynberg spiderhead reproduces
from seed. Once the seed ripens it is shed from the older flowers
and falls to the ground. The seeds are small, hard, oval nuts covered
by a fleshy layer called the elaisome. The elaisome layer attracts
ants that carry the seeds to their underground nest where the elaiosme
is consumed. The seeds remain in the nest until conditions are right
to germinate. This is one fascinating way of that the plant reseeds
itself. S. cyanoides is also adapted to survive fires, which
occur in the fynbos biome, by resprouting. It has an underground
rootstock that survives the fires. Although the above-ground parts
of the plant are burnt, new shoots develop from the rootstock. This
is another method by which the plant ensures its survival.
Growing Serruria cyanoides
Serruria cyanoides is propagated from cuttings or from seed.
Tip or heel cuttings are taken during spring or autumn. A rooting
hormone is applied to the semi-hardwood cuttings that will stimulate
rooting. The cuttings are rooted in a mixture of 50% milled pine
bark and 50% polystyrene granules. Good rooting will only take place
if the propagation house has misting and underbench heating. Rooting
will take place from 5 weeks onwards. Once the cuttings have rooted,
they are hardened off for 4 weeks before being planted. The rooted
cuttings should be planted in a fynbos type soil medium. Fynbos
type soils are usually nutrient poor and acidic. A suitable well-drained
fynbos soil mixture consists of a mixture of acidic river sand,
composted pine bark in equal parts and loam/topsoil.
Seed is collected from a mature flowerhead. The seed is sown in
late summer or early autumn as the effects of higher day temperatures
and cooler night temperatures play a vital role in initiating germination.
The seeds can also be exposed to short periods of high temperatures
followed by cooling water, which, by mimicking the autumn temperature
regime, stimulates the seed to germinate very well. The seeds should
be treated with a fungicide that prevents pre- and post-emergence
damping off. Transplant the seedlings as soon as they are large
enough to handle.
The young seedlings or potted cuttings should be grown in an area
that is well ventilated and well lit. The plants should preferably
be watered in the morning and may be fed with an organic seaweed-based
fertilizer. The young plants can be planted out into the garden
in autumn or during the cooler months. This allows the root system
to become established before the onset of the hot, dry summer and
gives the young plant a better chance to survive and thrive.
Serruria cyanoides is best suited to sandy soil, and will grow
well in fynbos or sandveld gardens. It is a small shrub, so plant
it among other slightly taller plants, or in the front of a bed
as an edging plant. Being a resprouter, it should not mind the occasional
pruning to keep it neat and compact. Plant in full sunlight and
ensure that the soil is well drained. Mulching with compost or woodchips
during summer will keep the soil cool and help feed the plants.
References
- Milewskia, A.V. 1978. Habitat of threatened species of Serruria
and Protea endemic to the western Cape coastal flats. Journal
of South African Botany 44: 363-371.
- Paterson Jones, C. 2000. The protea family in southern Africa.
Struik, Cape Town.
- Rebelo, A.G. 1995. Sasol proteas. A field guide to the proteas
of southern Africa. Fernwood Press, Cape Town.
- Rebelo, A.G. 2000. Proteas of the Cape Peninsula. Protea
Atlas Project, National Botanical Institute, Cape Town.
- Vogts, M. 1982. South Africa's Proteaceae. Know them and
grow them. Struik, Cape Town.
Author: Trevor Adams
Kirstenbosch National Botanical Garden
June 2003
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