The Karoo sagewood is an attractive foliage plant with silvery,
scalloped leaves and heads of yellow flowers during spring and summer.
It forms a small tree up to 4 m in height and 3 m wide or grows
into a bushy, upright and straggling shrub.
Buddleja glomerata is fast growing and has an expected life
span of 17 years. Several stems develop at the base of the plant
and are covered in light brown, stringy bark. Young branches are
flat, angled, light green in colour and are covered with whitish
hairs whereas older branches are light brown.
young leaves are silvery green and fade to a bluish green when older.
Leaves are oblong, 127 x 2-26 mm, arranged in opposite pairs on
branches. The upper surface of the leaf is bluish green, rough textured,
wrinkled and sparsely hairy. The lower surface is covered with white
or brownish hairs and a clearly visible, thick midrib and lateral
veins. Leaf margins are scalloped, wavy and lobed.
Bright yellow flowers, in dense heads are carried in panicles at
the end of the branches, enhancing the foliage of the plant from
September to March. The minute flowers are borne in dense, round
heads. The yellow anthers of the stamens protrude from the flowers.
It has been recorded that the scent of the flower smells foul and
the smell is supposed to be that of a cockroach; the pollen of the
flower can cause sneezing, hence the common names cockroach and
kakkerlak, sneezebush and niesbos. The fruit is a
small, hairy capsule.
Distribution and Habitat
Buddleja glomerata occurs in the mountains of the Karoo from
Uniondale through Victoria West, Beaufort West, Willowmore, Graff-Reinet,
Pearson, Somerset East and Middelberg to Cradock and Fauresmith
in Free State. It is found growing naturally among rocks and dry
Buddleja glomerata is an attractive garden plant, resistant
to drought and frost. Plant in a sunny spot in the garden in well-drained
soil and allow enough space for it to spread. Add compost and water
well until established. During summer, water moderately and do not
over-water in winter. Being Karoo dwellers they are heat and cold
resistant, tolerating temperatures between - 5°C and 30°C.
Plants can be pruned after flowering to keep them tidy.
Derivation of name and historical aspects
The specie name glomerata is a Latin word meaning 'collected
into heads' and refers to the type of inflorescence. The genus was
named in honour of an amateur botanist and cleric, Adam Buddle (1660-1715).
The flowers attract useful insects such as bees and butterflies
to the garden.
Growing Buddleja glomerata
Buddleja glomerata forms is a focal point in any garden
bed and can be used as a windbreaker, filler plant, hedge, or planted
in a rocky outcrop. It has non-invasive roots. Compost the plants
each year during winter to early spring and add a slow release fertilizer
to the soil such as 3:2:1 or 3:1:5.
Buddleja glomerata is easily grown from cuttings. Take semi-hardwood
cuttings in October, treat with rooting hormone, Seradix no.3 and
place in a medium of bark and polystyrene. Place the cuttings in
a mist unit with bottom heat and mist. The cuttings will develop
roots within 30 days, then harden off and repot. It is not easily
grown from seed.
There are seven species of Buddleja in South Africa which
occur in the eastern parts of the country. Interesting species are
B. saligna known as the false olive, a fast-growing tree
of 10 m high. The leaves of the plant are used to treat coughs and
colds. Creamy white flowers attract insects to the garden during
August to January.
the weeping sage, is an evergreen shrub or small tree. The branches
have a drooping habit and flowers are borne in large panicles at
the end of branches. Flowers are scented, creamy white to orange-yellow
with an orange throat.
Other species include B. dysophylla, B. loricata, B. pulchella
and B. salviifolia.
References and further reading
- Joffe, P. 2003. Easy guide to indigenous shrubs. Briza
- Palmer, E. & Pitman, N. 1972. Trees of southern Africa.
Balkema, Cape Town.
- Van Wyk, B. & Van Wyk, P. 1997. Field guide to trees
of southern Africa. Struik, Cape Town.
Kirstenbosch National Botanic Garden