A tender, evergreen shrub, 1-2 m (3-6 ft.) in height, it has glossy, yellowish-green leaves, which are leathery in texture and studded with oil glands which smell of blackcurrants. White flowers appear in spring. A member of the rue family, it is highly aromatic, scenting the air wherever it grows in quantity.
History and traditions
A prized medicinal plant of the indigenous people of South Africa, its virtues were discovered by colonists of the Cape who introduced it to Europe at the end of the 18th century. In the 1820s the dried leaves were exported in some quantity to Britain and thence to America, to be included in proprietary medicines and used to flavor cordials. John Lindley in his Flora Medica, 1838, records that several species of Agathosma, collected as ‘bucku’, were “found to be an excellent aromatic stomachic and very efficacious as a diuretic. The infusion is much praised as a remedy in chronic inflammations of the bladder and urethra and in chronic rheumatism.” All of these uses remain valid in herbal medicine today.
Culinary
Gives a blackcurrant taste to soft drinks and cordials and is used to flavor a local liquor “buchu brandy”.
Related species
Several species are used, all indiscriminately termed buchu, or “buka”, meaning powder in the local language. A. betulina is held to be the most effective for medicinal purposes, A. crenulata, oval buchu, has ovate leaves and A. serratifolia, long buchu, serrated, lance-shaped foliage. These plants were once classified as “barosma” and the term “barosma powder” for buchu is still sometimes used.
Growth
Grown as a conservatory plant in temperate zones, a minimum temperature of 5°C (41°F) is required. Pot in ericaceous (lime-free) compost. It must not be overwatered, which can lead to rot, and should be cut back hard in spring to keep it in shape and control size. Grown outside in warm, frost-free regions, it needs well-drained, acid soil and full sun.
Parts used
Leaves, which are harvested when the plant is in flower, and dried.
Uses
Medicinal
The volatile oil contains up to 40% diosphenol, a strong antiseptic. Used internally for urinary infections, especially cystitis, coughs and colds, rheumatism, arthritis and digestive disorders. Applied externally for bruises and sprains.
Household
Made into a powder to deter ants and other insects.
