Aulax umbellata is a slender shrub, up to 2.5 metres tall,
with bright yellow flowers contrasting vividly with the purplish
brown young foliage around the flowers during summer (from November
umbellata is one of the three species which form the genus Aulax,
the other two being Aulax cancellata, the channel-leaf featherbush
and Aulax pallasia, the needle-leaf featherbush. The genus
name is from the Greek aulax, a furrow. This refers to the
channelled leaves of Aulax cancellata. The species name umbellata
refers to the umbel shaped, nearly flat female flowerheads.The
plants of the genus Aulax are dioecious, with separate male
and female plants. The flowers of the male plants are bright lemon
yellow, arranged in small lax spikes, which open over a period of
several weeks. The new leaves of some of the plants are a beautiful
purplish brown from early September, slowly fading to green after
the end of the flowering period. The leaves of Aulax umbellata
are more or less needle shaped, but considerably wider than the
other two species, and this is the main distinguishing characteristic
for the species.
The images below are of a narrow leafed form collected near Kleinmond.
Female flowers of narrow leafed form
on narrow leafed form
Aulax umbellata is part of an ancient plant family, the
Proteaceae, which had already divided into two subfamilies, the
Proteoideae and the Grevilleoideae, before the break-up of the Gondwanaland
continent about 140 million years ago. Both these subfamilies occur
mainly in the Southern Hemisphere. In southern Africa there are
about 360 species, of which more than 330 species are confined to
the Cape Floral Kingdom, a relatively tiny portion of South Africa
between Nieuwoudtville in the northwest and Grahamstown in the east.
The extreme diversity of growth habits, flower forms and colours
prompted the botanist Linnaeus to name this family after the Greek
god Proteus, who could change his shape at will. Other well-known
genera of the Proteaceae are Leucospermum with brightly coloured
pincushion flowers, Protea with some of the most spectacular flowers
imaginable, Leucadendron with decorative woody cones and
Serruria, of which Serruria florida, the blushing
bride, with its beautful pale pink flowers is the most well-known.
umbellata occurs mainly on coastal lowlands in the Western Cape
province, from Kogelberg to Stilbaai, where it often forms dense
stands. The plants grow in very well drained sandy soil.
The pollen of Aulax umbellata is not wind dispersed and
although there is no nectar in the female flowers, the pollination
is done by insects. The resulting fruits are small nuts, usually
covered with long white hairs, only a few of the fruits in the female
flowerheads are viable. The seeds are kept for up to six years in
the flowerheads, but two year old seed shows the highest germination
percentage, this declines the older the seed becomes.
Growing Aulax umbellata
Aulax umbellata is sown from the middle of March, when the
day temperature starts to drop. The difference between the day-
and night temperatures should be about 15ºC, the night temperature
being the most important, preferably not above 10ºC. The seed
is sown in open seedbeds, in a light, well drained soil and covered
with a layer of sand (about 1 cm or 1½ times the size of
the seed). The bed is then covered with a grid to protect it against
attacks from birds and rodents. The seed will germinate three to
four weeks after sowing.
Aulax umbellata prefers to grow in a well drained sandy
soil with a layer of mulch of about 3 cm thick around the plants
to keep the soil moist and the roots cool. The root system is very
sensitive and should not be disturbed by loosening the soil once
the plant has settled and is growing. Like all Proteaceae, it needs
full sun and free air circulation. Plants generally take three or
four years to flower from seed.
Aulax umbellata shrubs are quite hardy and do not suffer
much from pests. The most harmful and destructive diseases are fungal.
Most losses occur during the summer months when a virulent root
fungus (Phytophthora camphora) can attack the plants. Control
through the use of fungicides in the garden is difficult and expensive.
By the time the plant shows distress, it is normally too late to
arrest the problem. The best methods of control are cultural, i.e.
water plants early in the morning; keep soil surface cool by mulching;
remove diseased plants immediately; do not over-water in summer
and prune and remove diseased material.
Aulax umbellata 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. Natural fires occur mainly in late summer
or autumn and are followed by the first winter rains, which provide
the moisture the young seedlings need to grow to a size at which
they can survive the long, hot summer. The fire itself, as well
as the smoke it produces, is thought to play a role in damaging
the thick seed coat of the small nuts and stimulating the germination
- The inflorescence morphology and systematics of Aulax (Proteaceae)
by J.P. Rourke, S. Afr. J. Bot., 1987, 53(6).
- 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.
- Grow South African Plants, compiled by Fiona Powrie.
Kirstenbosch National Botanic Garden,