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Leucadendron salignum is the most widespread species of
the family Proteaceae, occurring in a large part of South Africa.
It is common from Port Elizabeth in the east, to north of Ceres
in the west. It occurs on a wide range of soil types, from sea level
to an altitude of 2000 m and is quite variable in leaf size as well
as leaf- and bract colour. Leucadendrons are dioecious, i.e. separate
male and female plants. This is unusual in the protea family. Its
long flowering season (May - Dec), coupled with colourful leaves
and bracts surrounding the flowers, make this species an attractive
garden plant.
Leucadendron salignum is a multi-stemmed shrub with a persistent
rootstock, which enables it to resprout after fire. In its natural
conditions it grows to a height of 0.75 to 2 m. The variability
of growing conditions, from mild winter temperatures to snow and
frost near mountain tops, as well as the variability of leaves and
bracts, from greenish-yellow to vivid orange-red, have made this
species an excellent candidate for breeding. In addition, this species
adapts well to vigorous pruning, which makes it suitable for the
production of cut foliage on a large scale.
These characteristics have made the species a natural choice for
the wild flower industry. There are a range of plants in cultivation,
which differ markedly from the usual parent species, most often
in growth form, leaf- and bract colour and flowering time. They
may be either selections, known as 'cultivars' or hybrids, i.e.
'crosses' between species. Many hybrids and cultivars have been
produced in South Africa, New Zealand, Australia and other countries
growing Proteaceae.
At Kirstenbosch only a few of the hybrids are grown, mostly L.
x 'Safari Sunset', a hybrid of L. laureolum x L. salignum.
This is one of the best known leucadendrons and an export flower
crop in several countries. It is a tall, erect and vigorous shrub
up to 2.5 m high. It produces large deep-red bracts on long stems
from autumn through to late spring. These flare open to show cream
centres when flowering.
L. x 'Silvan Red' is a hybrid of the same two species with
a slightly lighter colour than ''Safari Sunset' and although usually
hardy, is not as frost hardy as 'Safari Sunset'.
Growing Leucadendron salignum
Cultivars and hybrids can only be propagated vegetatively. Cuttings
have to be 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 cuttings grow fast
and are ready to be planted out after a year.
Author: H G Jamieson
Kirstenbosch
November 2000
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