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Surely the best known protea, prized worldwide as a magnificent
cut flower and in South Africa honoured as the national flower.
Protea cynaroides is part of an ancient plant family, the
Proteaceae, which had already divided into two subfamilies before
the break-up of the Gondwanaland continent about 140 million years
ago. Both subfamilies, the Proteoideae and the Grevilleoideae, occur
mainly in the southern hemisphere. In southern Africa there are
about 360 species, mainly from the subfamily Proteoideae, of which
more than 330 species are confined to the Cape Foral Kingdom, between
Nieuwoudtville in the northwest and Grahamstown in the east. Protea
cynaroides belongs to the genus Protea, which has more
than 92 species, subspecies and varieties. Other well-known genera
of the Proteaceae are the Leucospermum with the brightly
coloured "pincushion" flowers, Leucadendron with
yellow or red-brown foliage and Serruria, of which the Serruria
florida or "Blushing Bride" with its pale pink flowers
is widely used in bridal bouquets. Plants in the subfamily Grevilleoideae
occur mainly in Australia.
The
amazing variety in plant size, habit, flower size and colour of
the genus Protea was the reason it was named after the Greek
god Proteus, who could change his shape at will. The flower
bud of Protea cynaroides looks remarkably like the globe
artichoke vegetable with the Latin name of Cynara scolymus
and this led the botanist Linnaeus to give it the species name
cynaroides.
Protea cynaroides has one of the widest distribution ranges
of all the Proteaceae and occurs from the Cedarberg in the northwest
to Grahamstown in the east. It occurs on all mountain ranges in
this area, except for the dry interior ranges, and at all elevations,
from sea level to 1500 meters high. The combination of the different
climatic conditions with the large range of localities has resulted
in a large variety of leaf- and flower sizes, as well as flower
colours and flowering times. The different forms retain these characteristics
even when grown under the same conditions on a commercial scale.
This has made it possible to grow Protea cynaroides as a
cut flower for a wide variety of export markets, where the flowers
are needed at different times of the year. This South African protea
is now grown in large quantities in New Zealand, Australia and Hawaii.
In Mediterranean climates in Europe, America en Australia it can
be grown successfully as a garden plant in the right type of soil.

Protea cynaroides is a woody shrub with thick stems and
large dark green, glossy leaves. Most plants are one metre in height
when mature, but may vary according to locality and habitat from
0.35 m to 2 metres in height.
The "flowers" of Protea cynaroides are actually
flower heads with a collection of flowers in the centre, surrounded
by large colourful bracts. The flowerheads vary in size, from about
120 mm to 300 mm in diameter. Large, vigorous plants produce six
to ten flower heads in one season, although some exceptional plants
can produce up to forty flower heads on one plant. The colour of
the bracts varies from a creamy white to a deep crimson, but the
soft pale pink bracts with a silvery sheen are the most prized.
Growing Protea cynaroides
Protea cynaroides can be propagated from seed or from cuttings.
The stems have to be thick and strong to carry the heavy flower
heads, this makes the taking of cuttings quite difficult, but good
colour forms or cultivars have to be propagated from cuttings.
Cuttings are made from semi-hardwood, 6-10 cm long, of the current
season's growth. The cuttings are dipped for about four seconds
in a rooting hormone solution and placed in a growing house with
bottom heat (25ºC) and intermittent mist. The rooted cuttings
are potted up when the roots are well developed and planted out
in the late autumn in South Africa, or in spring in colder areas.
The large nut-like seeds have to be treated during storage with
a systemic fungicide with the active ingredient of metalaxyl (Apron)
and sown from the middle of March, when the day temperature starts
to drop. The seed is sown in open seedbeds, in a light, well drained
soil and covered with a layer of sand (about 1 cm or 1 1/2 times
the size of the seed). The bed is then covered with a grid against
the attacks from birds and rodents. The seed will germinate three
to four weeks after sowing.
The plants are generally about four or five years old from seed
before they flower. On older plants the side shoots tend to be quite
short, so to encourage the development of new shoots and long stems,
the stems bearing old flower heads should be cut back to ground
level. Older plants also tend to become woody and should be cut
back to ground level, where they will sprout again from the thick
underground rootstock.
Protea
cynaroides occurs in fire prone vegetation, where natural fires
occur every ten to thirty years. This 'Mediterranean' type of vegetation
grows in soils with very low amounts of nutrients. These nutrients
are used up by the plants during their lifetime and need to be returned
to the soil to provide the food for a new generation of plants.
Protea cynaroides is adapted to survive the fires by its
thick underground stem, which contains many dormant buds; these
will produce the new growth after the fire.
The flowers in the centre of the flower head open over a fairly
long period of time, which makes it such a stunning sight in the
garden for weeks at a time as well as a long lasting cut flower.
The flowers are pollinated by Scarab Beetles and Protea Beetles
and many other insects, as well as by birds. The birds are attracted
by the nectar as well as by the insects visiting the flowers.
The large flower heads produce a disappointingly small amount of
good seeds, only 1 - 30 percent of flowers result in seed. The plant's
need to produce nutrient-rich seeds in a nutrient-poor environment
is thought to limit the amount of seeds it can produce. The seeds
are quite large nuts, covered by hairs and stay in the old flower
head for a year or more. They are released after a fire and dispersed
by rodents and birds.
Books to read:
The Proteas of Southern Africa by J.P. Rourke.
South Africa's Proteaceae by Marie Vogts.
Sasol Proteas, a field guide to the Proteas of Southern Africa
by Tony Rebelo.
The Protea Growers Handbook by Lewis Matthews.
H.G. Jamieson.
Kirstenbosch Botanic Garden
July 2001
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