
Whenever this beautiful shrub is placed on our specimen table,
it is often greeted with surprise as if it has never been seen before.
It is easy to overlook, even when it is in flower, because it grows
tall and presents its lovely white flowerheads above our heads.
Description:
Brunia
albiflora is a tall, slender, single-stemmed but well-branched shrub,
reaching 2-3 m in height. The long, slender branches are densely
leafy, with beautiful dark green foliage that resembles a pine tree,
but is much softer. The leaves are 10-14 mm long and narrow (0.7
mm diameter), narrowly lanceolate to linear, black-tipped and covered
with delicate hairs.
The flowers are tiny, and are crowded into tight spherical knob-like
inflorescences (± 15 mm wide) that are clustered into flat,
rounded heads. The knobby inflorescences are covered by scale-like
leaves, and before the white flowers break through, they are green
touched with black and silver and are also very decorative. Each
tiny flower is about 7 mm long, white with yellow stamens sticking
out, giving the inflorescence a yellowish tinge. They
open in a ring, starting at the outside and working inwards, and
age to a creamy yellow. In the early part of the season, one bush
usually shows the whole range of silver buds, ringed inflorescence,
full and ageing flowers. They are particularly noticeable on overcast
days when their white flowerheads seem to gleam amongst the dark
green foliage.
After flowering and fertilization, the flowers turn brown and drop
off. The knobby infructescence turns green, ageing to brown in time
and it stays on the bush for up to six years, so the remains of
the previous year's flowerhead can be seen lower down on the stem.
Flowering time is late summer to autumn (February-April).
Conservation status
Least Concern. Brunia albiflora is not threatened.
Distribution
Brunia albiflora is endemic to the Western Cape and occurs
from the Hottentots Holland Mountains to Hermanus. It has an extensive
distribution on the Hottentots Holland Mountains south of Kogelberg,
mostly on moist ground or in marshes on peaty sandstone, and is
common on the south-eastern slopes at the head of kloofs, usually
at an altitude between 330 and 1 000 m.
Ecology
Brunia
albiflora flowers provide both nectar and pollen. Pollen is
not produced in the same abundance as a wind-pollinated shrub, but
if you touch a flowerhead, you get pollen on you. And if you look
closely at the flowers you can see that a drop of nectar forms at
the base of each flower. They look like blobs of shiny purple gum,
but are drops of sweet liquid. I have seen sunbirds, bees, a few
beetles, ants and a wasp visit the flowers at Kirstenbosch-the sunbirds
were the most industrious, standing on a flowerhead while probing
the flowers for nectar and moving from one flowerhead to the next.
Brunia albiflora is serotinous, i.e. it stores its seeds
and accumulates them annually and they are released after the parent
is killed by fire. The garden at Kirstenbosch is not burnt, so the
infructescence eventually disintegrates and the seeds fall to the
floor below the parent and some of the seeds germinate on their
own. So although they are adapted to a fire-prone vegetation and
germinate much better after a fire, they are not entirely dependant
on fire for regeneration.
Derivation of the name
The genus Brunia is most likely named after a contemporary
of Linnaeus, the apothecary, Dr Cornelius Brun, who travelled in
Russia and the Levant, although it could also be in commemoration
of Dr Alexander Brown, a ship's surgeon and plant collector who
worked in the East Indies around 1690. The species name albiflora
means white-flowered. The Afrikaans common names are strictly applied
to Brunia noduliflora (= B.nodiflora), but are used
to refer to this species, some of the berzelias and other brunias
as well. Knopbossie means knob-bush, and refers to the knob-like
inflorescences that are a noticeable feature of berzelias and brunias.
Fonteinbossie means spring-bush as in water source because
these plants are often found growing near running water or in the
vicinity of a springhead. Stompies means little stumps, and
refers to the fact that if a fire sweeps through the population,
all that is left are small, blackened stumps.
The genus Brunia consists of seven species, all of which are
endemic to the Cape Floral Kingdom. The brunia family consists of
77 species in 12 genera: Brunia, Berzelia, Nebelia, Staavia,
Audouinia, Linconia, Lonchostoma, Mniothamnea, Thamnea, Pseudobaeckea,
Tittmannia and Raspalia. Although endemic to southern
Africa, it can't be said to be endemic to the Cape Floral Kingdom
because three species extend outside the Cape Floristic Region,
one as far as southern KwaZulu-Natal. It is a variable family; Audouinia
capitata and Tittmannia esterhuyseniae look like ericas,
Staavia dodii looks like a daisy, Lonchostoma spp.
look like something from the Thymelaeaceae family, Staavia globosa
has been mistaken for a phylica and Linnaeus himself mistook a coneless
twig of Widdringtonia as the type specimen for Brunia
nodiflora, now B. noduliflora . Those species relatively well known to gardeners
or buyers of cut flowers in the Cape are various species of Brunia,
and Berzelia, Nebelia paleacea and Staavia radiata.
Only about a quarter of the species in this family are locally
frequent where they occur, the rest are rare, often confined to
the upper slopes and in isolated patches of a few individuals. Many
of the members of this family show a lack of reproductive vigour,
and are difficult to propagate from seed and keep alive in cultivation.
Research has shown that more than 20% of the pollen grains of the
worst offenders show irregular appendages and distortions in shape
or a reduction in size, which suggests that they are not viable.
It appears that this family is slowly heading towards extinction,
not, for once, because of mankind, but because it has reached
the end of its natural lifespan and is in a state of senescence.
The brunia family is an ancient family. Actinocalyx bohrii,
a fossil flower from the Upper Cretaceous (70-80 million years ago)
of southern Sweden shares many characteristics with the Bruniaceae,
which indicates a great age for the ancestral line of this family.
Recently, fossil pollen that matches modern Bruniaceae pollen has
been found in early Tertiary and late Cretaceous deposits in northern
Namaqualand, that is between 65 and 97.5 million years ago, roughly
the time between the dinosaurs disappearing and the first primates
appearing. This confirms the considerable age of this family in
southern Africa. The wood of the Bruniaceae is very primitive, although
its other features are not. It has no other close relatives in Africa
or on the fragments of Gondwana. The diversity of this family and
its limited geographical range suggest that it has been isolated
at the southern tip of Africa for a long time. There is no indication
where the ancestral stock originated, nor how it got to southern
Africa. Its lack of Gondwana relatives could be because it appeared
here when the fragments were too far apart to be reached by chance
dispersal, or it could be that because this family is in a state
of decline, its other relatives have already gone extinct
and the southern African members are the only survivors. The Bruniaceae
has been placed with the Grubbiaceae (an endemic Cape family) near
the order Ericales. It is now thought to be a sister group to the
order Dipsacales, including the Dipsacaceae (teasel and scabiosa
family); the two groups are thought to have diverged around 57 million
years ago.
Uses
Brunia albiflora is a lovely cutflower, and an excellent
filler. Just the green stems can be cut as foliage, or the inflorescences
can be cut at whatever stage the beholder considers them to be attractive!
As it is a tall plant, long stems are easily achieved.
Because it is such a good green filler, it is harvested, sometimes
quite aggressively, from farms in its distribution range. A study
by Rebelo & Holmes (1990) showed that populations that are heavily
plucked, i.e. had more than 90% of their foliage removed, had no
seed reserves so that the populations would likely not recover if
burnt. Furthermore, plants that are heavily plucked can be killed.
In some cases up to 50% of them died although in a well-managed
population, only 8% died during the study period. Brunia albiflora
seems unable to regenerate from old wood that has lost its leaves.
Therefore, if a branch is cut off below the lowest leaf-bearing
shoot, that branch will die. In cases where a plant is still young
and consists of a single leader, cutting below the leaf-line will
kill the whole plant. To manage populations in a sustainable manner,
cutflower producers should ensure that they never remove more than
80% of all flowerheads, don't cut below the leaf-line, and that
if the previous year's seeds are removed, they should be stored
and not discarded. In this way the seed can be replaced in the event
of a fire.
Growing Brunia albiflora
Treat Brunia albiflora like a typical fynbos plant, e.g.
a protea, pincushion or conebush and you should have success growing
it.
Grow it in well-drained, acidic soil, in a sunny position, don't use strong chemical fertilisers or manure, water it well, particularly in winter and make sure that excess water drains away.
It is most likely tender to frost, but should survive the odd
cold snap of 0 to -1°C.
Propagate
Brunia albiflora by seed sown in autumn. Seed of Brunia
albiflora has a naturally low percentage germination, but being
a fire-adapted plant, treating the seed with the Kirstenbosch Instant
Smoke Plus Seed Primer shows a marked improvement in the number
of healthy seedlings. Seed should be harvested from the previous
year's flowers. Use a well-drained, acidic medium suitable for fynbos
plants e.g. roughly equal parts river sand and decomposed pine bark
or well-rotted, manure-free compost and about 20% topsoil. Cover
the seeds lightly, using the sowing medium and water gently to avoid
disturbing the seeds. Keep moist but not wet. The seed should start
to germinate in about six weeks. The young seedlings are very small
and delicate and need to be nursed through their first year. Place
the tray(s) in good bright light but not in direct sun, e.g. under
an opaque roof or shade-netting and in a well-ventilated area. Water
by hand, and keep the medium well-watered but take care not to over-water.
The seedlings grow slowly during winter and only start to increase
in size as spring approaches. They can be potted up in spring, but
only if they are between 10-20 mm tall and have developed their
secondary leaves. Pot them into small pots or multi-trays-they often
die when placed in large containers, probably because the soil remains
too wet. Use the same fynbos mix that you used for the seed. Feed
the seedlings every two weeks with a diluted, liquid, seaweed-based
fertilizer. Keep them in the nursery all summer in the same conditions
i.e. bright light but not direct sun, and well ventilated. They
can be placed in a larger container, or planted out into the garden
the following autumn. Regular pruning or pinching out the shoots
will result in increased branching and a more rounded bush with
more flowers-just remember not to prune below the leaf-line.
Brunia albiflora can also be propagated vegetatively. Cuttings
should be taken in autumn or spring from actively growing, healthy
shoots. The best results are achieved from side shoots not longer
than 100 mm, taken as heel cuttings. Tip cuttings can also be taken.
Gently remove the needle-like leaves from the lower 20-30 mm of
the cutting and dip the heel or cut end in a rooting hormone used
for semi-hardwood cuttings. You can use a powder or liquid rooting
hormone. Place the cuttings in a rooting medium consisting of equal
parts of 6 mm milled pine bark and polystyrene balls. The polystyrene
aerates the mix, which is crucial for healthy root development.
Some growers have had success using washed peat and coarse river
sand. Use a shallow or compartmentalized tray for the cuttings,
and make sure that the cleaned stem is submerged in the medium.
Place the trays where they will receive regular misting or fogging;
this prevents the leaves from drying out. Heated benches are also
recommended as the warmth accelerates the rooting process. Rooting
takes from six weeks to a few months. We have found that some cuttings
do not develop roots, even after a few months-instead we find white
cell aggregations on the lower stem. This is callus tissue, which
may not produce roots. We remove these cuttings and slightly damage
the ends then re-treat them with rooting hormone and place them
into fresh rooting medium and have had good results with roots developing
rapidly and aggressively.
The roots are fine and delicate, so rooted cuttings should be carefully
removed and transplanted into individual containers. Use a well-drained,
acidic mix suitable for fynbos plants. Place the newly rooted cuttings
in a cool, shaded, well-aerated spot for them to adapt to their
new medium. Feed them regularly with diluted organic fertilizer.
When they are actively growing, place them in full sunlight.
References and further reading
- Dyer, R.A. 1944. Brunia albiflora. The Flowering Plants
of South Africa 24: t. 928
- Goldblatt, P. & Manning, J. 2000. Cape plants, A conspectus
of the Cape flora of South Africa. Strelitzia 9. National
Botanical Institute, Pretoria & Missouri Botanical Garden
Press.
- Goldblatt, P. & Manning, J.C. 2002. Plant diversity of the
Cape Region of southern Africa. Annals of the Missouri Botanical
Garden 89: 281-302.
- Hall, A.V. 1987. Evidence of a Cretaceous alliance for the Bruniaceae.
South African Journal of Science 83: 58, 59.
- Jackson, W.P.U. 1990. Origins and meanings of names of South
African plant genera. University of Cape Town Printing Department.
- Plants of southern Africa: an online checklist. http://posa.sanbi.org
- Rebelo, A.G. & Holmes, P.M. 1990. Reap or rape? Exploitation
of the coffee bush Brunia albiflora. Veld & Flora 76:
45-47.
- Scott, G. 1989. Bravo for the Bruniaceae. Veld & Flora
75: 105, 106.
- Smith, C.A. 1966. Common names of South African plants. Memoirs
of the Botanical Survey of South Africa No 35.
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Alice Notten
(propagation information provided by Anthony Hitchcock)
Kirstenbosch National Botanical Garden
April 2004
(Updated February 2010)
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Reader's Comment:
In October 2012 Terrence Beavis wrote:
I am resident in Blenheim New Zealand. I have read about Brunia Albiflora on the website " Plantzafrica.com".I note on the website that Brunia will tolerate temperatures down to -1 degrees.I have three Brunia Albiflora growing in my garden here and have had temperatures down to -8 degrees of frost with no damage to foliage or flowers.
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