Agathosma mucronulata is an attractive evergreen aromatic
shrub, belonging to the Rutaceae family. This family also includes
the Cape chestnut, Calodendrum capense and the citrus fruits.
The common characteristic is the presence of oil glands, visible
as tiny dots, on the leaves and fruits.
Agathosma mucronulata forms a neat, compact, rounded upright
shrub 0.8-1 m tall. The leaves, which have a pungent almost turpentine-like
scent, are spirally arranged around the stem and the apex of the
leaf terminates in a sharp point. Masses of white flowers are produced
during winter to spring (July to October). The flowers are small,
with five petals arranged in a star, and are borne in lax terminal
clusters. Each white petal is marked with 5 or 6 brown dots, which
adds to the attractiveness of the flower. During the flowering period,
the bush comes alive with bees and butterflies, which visit and
pollinate the flowers. The three-chambered seed capsules are formed
after pollination. These ripen during early summer (October-November)
and when ready, burst open to release the seed with surprising force.
This phenomenon is known as ballistic dispersal. Buchu seed is best
collected when the seed capsule is very hard, just before it splits
open. This is difficult to judge, and covering the branch ends with
netting to capture the seed as it is catapulted out of the seed
capsule is also effective.
Agathosma mucronulata occurs in mountain fynbos on the drier
middle slopes around the Western Cape town of Uniondale, in the
south-eastern part of the winter rainfall region of South Africa
in Western Cape.
There are about 140 species in the genus Agathosma and most
of them are found in the Western Cape. The genus name Agathosma
is derived from the Greek agathos meaning pleasant or good
and osme, scent or smell, referring to the pleasant scent emitted
by the leaves and fruits which is caused by the presence of volatile
oils in the leaves and fruit. The species name mucronulata
is derived from the Latin for sharply pointed and refers to the
shape of the leaf with its pointed apex.
Agathosma mucronulata is not a medicinal plant. The true
buchus are A. betulina and A. crenulata. These two
species are now grown commercially and the oil is extracted for
use in cosmetics, soaps, food colourant, and medicinally for the
treatment of stomach complaints, kidney and urinary tract disorders,
and for colds, flu, coughs and other chest complaints.
Growing Agathosma mucronulata
Agathosma mucronulata does best when planted in full sun
and needs adequate water during the hot summer months. It requires
a soil that is well drained, and enriched with well-rotted compost
(leaf mould) and a well-balanced slow-release fertilizer (3:2:1).
It is slow growing and needs space in the garden bed to allow it
to develop to its full potential, without being squashed by other
faster growing plants.
Planting buchus into the garden is best done after the first good
winter rains have fallen (May to July). Buchus respond well to fairly
dense plantings, so plant a number of the same species fairly close
together e.g. in groups of three of five, and in this way you will
get a more dense and floriferous bush and help to retain soil moisture.
A good thick mulching of well-rotted compost applied once a year
will reduce weed growth, keep the soil temperature even, and conserve
moisture during the hot dry summer.
Buchus occur naturally in mixed fynbos and are ideally suited to
the fynbos garden, grown with other fynbos plants such as proteas,
ericas, restios, pelargoniums, vygies, helichrysums, phylicas and
felicias. Agathosma mucronulata also makes an attractive
border plant, it is a useful filler plant, and it can be used in
the rockery. To enjoy the scented foliage, plant it beside a path
or in a container on a patio, where it will release its fragrance
whenever it is touched. Other species suitable for the garden include
Agathosma lanceolata and
Buchus can be grown from seed or cuttings. Fresh buchu seed should
be sown in autumn (April). The seed is sown into a tray containing
a well-drained medium of equal portions of sand, loam and compost.
Use some of the medium to cover the seed, and water. Place in a
covered area with good light and free air circulation and keep damp.
Germination occurs in 1 to 2 months. When the first four true leaves
have developed, the young seedlings are pricked out into 0.5 litre
bags containing a well-drained, humus-enriched potting medium (e.g.
2 parts leaf mould : 1 part coarse sand). Feed regularly but sparingly
with a well-balanced fertilizer. Pinch out the growing tips of the
seedlings to encourage bushy growth. Flowers are produced after
Cuttings have the advantage of producing a larger plant that will
reach flowering size sooner than seedlings. Tip cuttings, 50-70
mm, are taken from the current season's growth in spring (September
to November). Prepare the cuttings by making a clean cut below the
node and remove a third of the foliage. Dip the base of the cutting
in a rooting hormone such as Seradix 2. Plant the cuttings firmly
in a medium of 50% bark and 50% polystyrene. Ideally these cuttings
should now be placed in a well-aerated propagation unit with bottom
heat of 24° C and intermittent mist. Rooting occurs in 9 to
11 weeks and a weaning period of 2 weeks is recommended. Carefully
pot the rooted cuttings into a well-drained, humus-enriched potting
medium (e.g. 2 parts leaf mould : 1 part coarse sand). Feed regularly
but sparingly with a well-balanced fertilizer. Yellow leaves can
be treated with an application of iron chelate. Plants will be ready
for planting in 7 to 8 months.
- 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, Missouri.
- LEISTNER, O.A. (ed.). 2000. Seed plants of southern Africa:
families and genera, Strelitzia 10. National Botanical Institute,
- JACKSON, W.P.U. 1990. Origins and meanings of names of South
African plant genera. University of Cape Town.
Norma Jodamus & Alice Notten
Kirstenbosch National Botanical Garden