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This large, sturdy, Cape reed will introduce a true autumn feeling
in your garden with its striking orange-brown, female inflorescences
during April, May and June.
Description
Restio
dispar is a medium to large, reed-like plant, which can grow
to a height of 2 m when grown in a reasonably fertile soil with
the normal amount of water given in a garden. The plants have strong,
upright stems and grow in a more or less tufted form with spreading
rhizomes. When mature, the plants can reach a diameter of about
1 m at ground level after three years' growth. The stems branch
from about halfway up with a large amount of long inflorescences
at the top of the branches of the female plants.
In contrast to most reed species, the female plants of R. dispar
are much more showy, sturdy and larger than the male plants. The
male plants are slightly smaller than the female plants, the inflorescences
are inconspicuous and the whole plant looks a bit messy and weak.
However, plants of both sexes are strong-growing and can easily
reach an age of more than one to seven years. The main growth period
is at the end of the Cape winter (August-November).
Distribution
Restio dispar is a true Cape reed and occurs only in a fairly
small area on the southwestern mountains in the Cape Floristic Region
from Bainskloof to Hermanus. The plants are generally found along
streams or amongst rocks, often forming large stands in deeper soils
at lower altitudes, from 5 to 1 200 m. The plants should be grown
with a regular amount of irrigation and are suited to cultivation
in gardens in the Southern Hemisphere. As with other reed species,
the roots are sensitive to a combination of frost and wet soil and
in the Northern Hemisphere should be grown in pots.
Name
The family name of Restionaceae refers to the Latin restis,
which means cord or rope and alludes to the use of the plants in
southern Africa. The more than 400 species in about 40 genera of
the Restionaceae family occur in the winter rainfall regions of
South Africa and Australia, with outliers in Africa, Madagascar,
Indo-China and Chile. The species name of dispar refers to
the dissimilar or unequal appearance of the male and female plants.
Ecology
Like
the other reed species, the male and female flowers are on different
plants and both are small and insignificant. The plants flower during
late April and early May. The male flowers are greenish yellow and
easily visible, whereas the female flowers are white and hidden
deeply within the large orange-brown bracts, except for the few
days the plants are in full flower and waiting to be pollinated.
The plants are wind pollinated. The wind distributes the pollen
from the free-hanging anthers of the male flowers to the female
inflorescence where the large bracts catch the pollen from the air
and funnel it towards the female flowers. Sometimes bees are present,
but always around the male plants, where they collect the pollen.
The seeds ripen in small capsules, three seeds to a capsule. When
the seeds are ripe, the capsule opens up and dispels the seeds.
The seeds are ready in November and are very pretty, fairly large
for a species of restio, triangular in shape and silvery blue-green.
Uses and cultural aspects
The economic use of plants of this family has been limited, as the
plants contain a large amount of tannin and so are grazed only as
a last resort by cattle and sheep. The species that have simple,
unbranched stems are sometimes used for thatching, while the species
with branched stems are used as brooms or (besems). The plants
have been introduced to horticulture and are available from specialized
nurseries.
Growing Restio dispar
This
species is best used in a fairly large garden as a plant in a large
border, planted behind a group of smaller plants. The plants fit
in with fynbos plants, other indigenous South African plants as
well as any other plants in a garden. They can be used as medium-sized
shrubs and provide the touch of grass-like plants now so fashionable
in landscaping. It is useful for group plantings in large landscaping
projects. The plants are especially suited to planting on a slope.
The plants are best grown from seed, which has a good germination
rate and germinates even better if treated with smoke or 'Instant
Smoke Plus' seed primer. This species must be grown in full
sun, prefers a well-drained soil and plenty of air movement. The
plants adapt to a large variety of soil types. The best time for
planting restios is at the beginning of the rainy season, as the
plants need regular watering during the first six weeks to two months
after planting. After this initial period the plants can survive
with a little additional watering but grow better with a normal
garden watering regime. They may be fed with organic seaweed-based
fertilizers, or by sprinkling the surrounding soil with a small
amount of ammonium sulfate during the growing season. Restios will
respond to regular watering by showing more robust growth, but they
are essentially plants which are adapted to a long, dry season.
This is a fast-growing species that will be about 1 m high one
year after sowing and will have formed a handsome plant three years
after sowing. The plants produce a new growth flush in the centre
of the plant every year. The individual stems start to deteriorate
during the third year but by that time already two new flushes of
growth will have appeared for the yearly renewal of the plant. This
governs the maintenance of the plant, which really only needs a
regular removal of the brown, dead stems on at the outside part
of the plant.
References
Andrews, S. & McClintock, D. 1982. Notes on Restio suberticellatus.
The Plantsman 37: 230-233.
Brown, N., Jamieson, H. & Botha, P. 1998. Grow restios.
Kirstenbosch Gardening Series, National Botanical Institute, Cape
Town.
Dorrat-Haaksma, E.& Linder, H.P. 2000. Restios of the Fynbos.
The Botanical Society of South Africa, Cape Town.
Linder, H.P. 1985. A conspectus of the African species of Restionaceae.
Bothalia 15: 3, 4.
Linder, H.P. 1991. A review of the southern African Restionaceae.
Contributions from the Bolus Herbarium 13.
Hanneke Jamieson
Kirstenbosch NBG
April 2003
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