The genus Serruria belongs to the protea family and was
named in honour of J. Serrurier who was Professor of Botany at the
University of Utrecht in the early eighteenth century. The specific
name aemula means rival presumably referring to its beauty.
The common name refers to the old flower heads, which turn bright
red and swell as the fruit ripens resembling a strawberry.
Serrurias grow on the mountains and flats of the southwestern Cape
from the Cederberg to near Mossel Bay.
Serruria aemula once occurred in huge stands on the Cape
Flats near Cape Town from Milnerton to Rondebosch. Sadly this beautiful
species has been reduced by farming and urban development, to a
few populations along road reserves and under power lines totalling
about 1 000 plants. Unless there is urgent and appropriate field
management of the few remaining natural populations, this species
will become extinct in the wild within the next few decades.
This plant is endangered due to extensive urbanization around Cape
Town and resulting destruction and fragmentation of its habitat.
Changes to the habitat by alterations in drainage, water pollution,
air pollution (acid rain), dumping and lack of a fire management
plan, pose serious threats to the remaining communities.
and infestation of natural areas by alien Acacia species
has negatively affected natural populations.
Management of alien vegetation under power lines through brush cutting
and spraying herbicides, have serious implications for the future
of the populations in the area.
The introduction of Argentinian ants poses another threat as they
outcompete indigenous ants, which carry the fruits (seeds) underground
and so protect the seeds prior to germination. If the fruit is not
stored underground it becomes susceptible to predation by rodents.
Predictions of climate change in southern Africa could have serious
consequences for temperature and rainfall patterns. The predictions
are that the effect of climate change on plant communities is not
easy to determine for individual species, but the long-term prognosis
is not encouraging.
Serruria aemula forms a sprawling, much-branched shrublet
reaching a height of 0.5 m. The leaves are finely dissected and
point upward and with its tangled branch structure produce an overall
woolly effect. Older plants consolidate their growth into a dense-growing
rounded shrub. The plant produces numerous solitary silky (silvery)
pink, sweetly scented flowers from July to October. These flowers
can cover the entire plant producing a spectacular display in spring
and early summer.
This species includes a number of different growth forms. The most
notable being a densely leaved and flowered variety called 'congesta'.
This form has not been seen in nature since the 1980's and is believed
to be extinct.
Serruria foeniculacea, which occurs at Rondevlei has also
been recognized as another form of S. aemula. S. foeniculaceae
has a typically lax growth habit by comparison.
NATURAL HABITAT AND ECOLOGY
Serruria aemula grows in deep acid sand at low altitudes
(20-70 m). It is exposed to wet soils and cool and mild conditions
during winter (0-18°C). The warm summer months are normally
hot, dry and windy (10-28°C) and the soils can become loose
The plants survive better if there is a good, closely growing community
consisting of a mixture of natural vegetation in a relatively undisturbed
state. These plants serve to protect each other and form a natural
vegetation cover that keeps the soils cooler and bind the sandy
soils. Typical examples of plants found in this community are Serruria
fasciflora (common pin spiderhead), Diastella proteoides
(Flats silkypuff), Leucospermum hypophyllocarpodendron (green-snakestem
pincushion), Leucadendron levisanus (Cape Flats conebush),
Erica mammosa (ninepin heath), E. ferrea, and restios
Serruria aemula is relatively short-lived and reproduces
from seed. Seeds are released within two months of flowering. The
seeds are small, hard-shelled, oval nutlets, covered by a fleshy
skin called the elaiosome. The elaiosome secretes a chemical substance
that attracts ants and they carry the seed to their underground
nests where they consume the elaiosome. The seed remains underground
safe from predators such as rodents until conditions are right for
them to germinate. Buried fruits will receive their cue to germinate
from subtle changes around them after fire has occurred. These include
increased changes in day/night soil temperature fluctuations once
vegetation cover has been burnt away. Other factors include increased
availability of oxygen once the ants abandon the nest and increased
pH in the nest.
Fire is therefore a necessary element in the life cycle of Serruria
aemula. The beneficial effects of fire can, however, have a
negative effect if fire occurs too regularly. This will reduce the
ability of the plants to produce a viable store of seed for future
Numerous honeybees and small butterflies were seen visiting the
flowers. The bees were carrying large pollen sacs on their hind
legs. It is assumed that they are the main pollinators.
Growing Serruria aemula
Serruria aemula is easily reproduced from tip or heel cuttings
taken in spring or autumn. Successful rooting depends upon having
good propagation houses with mist benches and under-floor heating.
Cuttings are rooted in a 50:50 mixture of 6 mm milled pine bark
and polystyrene balls. Applying a rooting hormone for semi-hardwood
cuttings will stimulate rooting. Rooting takes place from six weeks
onwards. Rooted cuttings are removed from the mist benches and hardened
off for a few weeks before planting. The hardened-off cuttings are
planted out into a potting medium made up for fynbos plants. A suitable
mixture consists of a mixture of acid river sand, composted pine
bark in equal parts and 205 loam/topsoil by volume.
Seed is collected as it is released from the flower head. Premature
removal of seed will result in failure. Seed is sown in late summer
or early autumn to harness the positive effects of higher variance
between day and night temperatures. Seed exposed to a short period
of high temperature followed by rapid cooling in water has been
known to germinate very well. The seed should be protected from
fungal pathogens by application of a fungicide designed to treat
pre- and post-emergence damping off.
Plants should be kept in a well-ventilated and lit area and preferably
watered in the morning. Plants that are consistently wet at night
will develop fungal infection. They may be fed every week with an
organic seaweed-based fertilizer.
Young plants should be planted in autumn or during the cooler months
for them to become established before the onset of summer. Plant
in full sunlight and ensure that the soil is well drained. Mulching
with wood chips or compost will keep the soil cool and help feed
INITIATIVES TOWARDS SURVIVAL
In situ conservation
main remaining populations occur under power lines managed by ESKOM.
The land has been given National Heritage Site Status because there
are a number of threatened Cape Flats plants growing on it. An advisory
committee comprising representatives from ESKOM, Cape Nature Conservation
Board, Kirstenbosch, Botanical Society and professional conservation
biologists, is working towards establishing appropriate land management
practices to ensure the survival of the remaining populations.
Ex situ conservation
Plants are being propagated and grown at the Kirstenbosch Botanic
Gardens for re-introduction to the damaged areas under the power
Plants are also grown for display in the gardens and are available
for sale at the Annual Plant Fair in March of each year.
Seed will be collected and stored in the Millenium Seed Bank at
Wisley. This seed is subjected to low temperatures where it can
be kept for long periods. The seed remains the property of the country
- REBELO, A.G. (Tony). 2000. Proteas of the Cape Peninsula.
Protea Atlas Project, National Botanical Institute, Cape Town.
- REBELO, A.G. (Tony). 1995. Sasol proteas. A field guide
to the proteas of southern Africa. Fernwood Press, Cape Town.
- VOGTS, M. 1982. South Africa's Proteaceae. Know them and
grow them. Struik, Cape Town.
Anthony Hitchcock and Trevor Adams
Kirstenbosch Nataional Botanical Gardens