Leucadendron laxum is a decorative member of the protea
family. This much-branched, dense shrub has a single stem at ground
level, with short branches clustered at the base of the plant. It
is evergreen, with small needle-like leaves and grows to between
1,5 and 1,75 m high in cultivation. It is dioecious (i.e. unisexual
with male and female flowers on different plants), and both male
and female plants produce masses of small bright yellow flowers
during spring and early summer (September to October). On the female
plants the flower-heads develop into very attractive small rosy-pink
cones resembling opening rosebuds, remaining decorative until the
seeds ripen during autumn (March) the following year. The cones
can be dried and used in dried flower arrangements or in Christmas
Leucadendron laxum occurs in dense stands near the most
southern point of the African continent, where the Atlantic and
Indian Oceans meet, where it grows on the level, damp ground in
the valleys between Hermanus, Bredasdorp and Agulhas. How much longer
the plants will be seen growing in the wild is not certain, as its
habitat is being drained and farmed. As a result its status in the
Red Data Book is: endangered.
Leucadendron laxum is pollinated by insects, which are attracted
by the slight, faintly unpleasant smell of the flowers. The fruits
on the female plants ripen about six months later and appear as
small, slightly mottled nutlets. These fall on the ground as the
cones dry out and open up. It is very unusual to find young seedlings
in between the mature plants and regeneration normally only takes
place after a fire.
Leucadendron laxum 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 stimulate the germination
Leucadendron laxum 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. More than 93 species,
subspecies and varieties, all of them woody shrubs, belong to the
genus Leucadendron. Other well-known genera of the Proteaceae
are Leucospermum with brightly coloured pincushion flowers, Protea
with some of the most spectacular flowers imaginable and Serruria,
of which the Serruria florida, the blushing bride, with its
pale pink flowers is widely used in bridal bouquets.
The genus name Leucadendron is from the Greek leukos,
white and dendron, tree, referring to the silver tree, Leucadendron
argenteum, on which this genus was based. The species name
laxum refers to the growth habit of Leucadendron laxum.
The Afrikaans common name vleirosie is very descriptive,
as it refers both to the habitat (a 'vlei' is a wet low-lying area)
and the most attractive aspect of the plant ('rosie' for rose-bud
like female cone).
Growing Leucadendron laxum
Leucadendron laxum is a worthwhile addition to the garden, where
it is shown to best advantage in dense plantings in a sunny spot,
where it will provide pleasure with its bright yellow flowers and
attractive cones. Its flowers, cones and foliage make it a useful
addition to flower arrangements.
Leucadendron laxum prefers to be planted in a damp situation
or needs to be watered regularly. Like all Proteaceae, it needs
full sun and good air circulation. Leucadendron laxum 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
Propagation of Leucadendron laxum is by seed sown from the
middle of March (autumn), when the temperatures start to drop. It
appears to be the difference between the day- and night temperatures
that triggers germination. This temperature difference should be
about 15ºC, but it is the night temperature that is the most
important. It is only after the night temperature drops to 10ºC
or lower that germination occurs. 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 attack from birds and rodents.
The seed will germinate three to four weeks after sowing and the
plants generally flower in their third or fourth year.
A Revision of the Genus Leucadendron (Proteaceae) by Ion
J.M. Williams.Contribution of the Bolus Herbarium No. 3. 1972.
- South Africa's Proteaceae: Know them and grow them by Marie
Vogts. Cape Town, Struik, 1982.
- Sasol Proteas, a field guide to the Proteas of Southern Africa
by Tony Rebelo. Vlaeberg, Fernwood Press, 1995.
- The Protea Growers Handbook by Lewis Matthews. Durban, Trade
Winds Press, 1993.
- Grow South African Plants, compiled by Fiona Powrie. Cape Town,
Kirstenbosch Botanic Garden,