One of the first signs that our long, hot summer is finally coming to an end is the appearance of buds on the late summer and autumn-flowering Plectranthus or spurflower (plectron=spur; anthos= flower). These free-flowering and easy, fast-growing plants have much to recommend them, particularly for gardeners who believe they do not have green fingers.
It is interesting to note that of the over 300 species distributed in Africa, India and Australia, those best suited to our gardens come from the Eastern Cape and southern KwaZulu-Natal. Plectranthus fruticosus was the first South African plectranthus to be grown at Kew from seeds collected by the young Scottish horticulturalist, Francis Masson, during a collecting trip to the southern Cape in 1773-74.
Plectranthus provide a colourful display in autumn gardens. Some species grow in heavy shade; some as groundcovers where they suppress weed growth, prevent erosion and help the soil retain moisture. Others grow as succulents in rockeries. Their succulent nature – which makes them such good house plants (both as pot plants & in hanging baskets) – is an adaptation to disturbance from animals and drought. A broken branch will quickly grow roots; plants desiccated by drought will soon revive after a shower of rain.
Shrubby species, such as the P. ecklonii and P. fruticosus, grown in large groups turn shady areas into stunning glades of blue, pink and white.
Many groundcovering species grow in shade, like P. ciliates ‘Drège’ with its sprays of dainty white flowers and leaves with dark purple undersides; and the variegated white P. madagascariensis ‘Lynne’.
Shrubs should be pruned in midwinter – they are rapid growers and will resprout as soon as the weather warms up. Cuttings are easily rooted and are best taken in spring or summer.
For more information on these beautiful and interesting plants, beg, borrow or steal a copy of Ernst van Jaarsveld’s Southern African Plectranthus and the art of turning shade to glade, Fernwood Press, 2006 – it is guaranteed to change your garden!
Text: Leonie Twentyman-Jones