Protea aristata E.Phillips
Common names: Ladismith sugarbush (Eng.); klein-den-suikerbos (Afr.)
Protea aristata would surely be among the five best-known South African proteas, even though it had a rather late documented discovery in the 1920s. It is a great wonder why it took so long for botanists to record such a beautiful and attractive plant, especially since it has been recorded growing along roadsides in the Ladismith surrounds. Its current recognition is largely owing to its stunning crimson-pink flowerheads, needle-like foliage and neat form. It could prove to be a future favourite amongst indigenous gardeners, as it is water-wise, considering increasing water scarcity in South Africa.
Protea aristata falls within the group of ‘true’ sugarbushes which are characterised by their large, obconic flowerheads. P. aristata is an erect, stocky, single-stemmed shrub that reaches 2.5 m in height and a diameter of up to 3 m when growing in areas that evade fires, while the stem diameter reaches 250 mm (Rourke 1980).
Stems are erect, hairless and 5–7 mm in diameter. Trunk bark is smooth and grey, whereas younger stems have light brown bark. Narrow, linear and erect needle-like leaves are arranged in an upright position on the stems. Leaves are 70–110 mm long and 2–3 mm wide, are flattened with the petiolar region slightly tapering and are hairless, glaucous (greyish green or blue) and smooth, with a black point at the leaf tip. The beautiful, reddish pink flowerhead is obconic (inverted cone) to bell-shaped, is 110–140 mm long and 100–120 mm wide. Flowering is mainly during the hot and dry summer months in the southern hemisphere, and occurs from October to as late as February, with December being the peak flowering period (Rourke 1980).
Fruits ripen quickly and are shed about six to nine months after flowering. According to Rourke (1980), arid natural habitats promote early release of seed. This could possibly be due to flowerheads drying out a lot faster than flowerheads on plants under cultivation. Wild seed may be collected by wild-seed collectors as early as April, but seed will be fully ripe by May. If not collected by this time, seed could be lost once flowerheads begin to open and disperse their seed. However, plants under cultivation retain old closed flowerheads for up to a year and allow more time for seed collection.
According to the website http://redlist.sanbi.org, checked on 21 December 2015, the conservation status of this plant is Vulnerable (VU) with a decreasing population trend. This status is largely due to too frequent fires which have caused a decline in the population numbers, especially since they are slow to mature. It is also an endemic species, being confined to the Swartberg region. The population of Protea aristata is estimated to have a maximum of 6 000 plants, with no subpopulation consisting of more than 1 000 individuals. Interestingly, Rourke (1980) commented that many people often thought P. aristata to be rare due to its scattered localities and that it being rare was most definitely not the case. A mere 30 years later, P. aristata is now classified as Vulnerable.
Distribution and habitat
Protea aristata is endemic to the Klein Swartberg (a misleading name for the high, rugged mountains of the western Swartberg), between Bufffelspoort and Seweweekspoort in the Western Cape, and grows on ledges of inaccessible steep krantzes and rocky sandstone slopes at an altitude of 750–2 000 m.
Derivation of name and historical aspects
The Proteacae family comprises of 14 genera and 352 species in South Africa. The genus name Protea is derived from the Greek Proteus, a mythological god who had the ability to take on many different forms. This genus name was given by Carl Linnaeus in 1735 and alludes to the variation of form within the Protea family. However, it is unlikely that Linnaeus would have seen the great variability of the genus by 1735 and it could be possible that there is a different derivation of the name. The alternative derivation could be from the Greek Proteia, which is derived from protos meaning ‘before’ or ‘first’ and indicated ‘first prize’ or ‘first place’. This ‘first prize’ could allude to the sheer beauty and powerful impact of impressive protea flowers on botanists, explorers and collectors. The species name aristata is derived from Latin and means ‘awned’, referring to the prominent awns on the perianth limbs (Jackson 1990).
It is a great wonder why Protea aristata, so readily accessible around the town of Ladismith and spectacular in beauty and form, was only formally documented by botanists in 1928, and that the general public has only been aware of this plant since the 1960s. In December 1928, T.P. Stokoe and R. Primos collected a specimen in bud from the Seweweekspoort near Ladismith and this date marked the botanists’ first acquaintance with P. aristata.
Protea aristata is considered a reseeder since fire kills the plant entirely and only seed survives; it has the adaptation of serotiny. In this adaptation, seeds are withheld in cones or flowerheads on the plant until fire sweeps through in late summer. Too frequent fires can have a devastating effect on Fynbos plants that rely on seed to rejuvenate populations, and fires should on average only burn every fifteen years to allow plant species to reach reproductive stages and produce sufficient seed. John Rourke has described witnessing P. aristata in the wild on inaccessible ledges, making them able to escape periodic fynbos fires and live to the age of 50 years or more. Birds are the main pollinators of this plant, possibly the Sugarbird is the main pollinator. Seed is stored on the plant until the flowerhead opens to release seed which are thereafter dispersed by wind.
Interestingly, when the leaves or stems are picked, an offensive and unpleasant sulphuric odour is produced, making it unsuitable for the cutflower trade. However, a hybrid between P. aristata and P. repens named ‘Venus’, has successfully been cultivated for the cutflower industry.
Growing Protea aristata
Although Protea aristata is slow-growing, this compact and neat shrub will be one of the longest lived proteas in the garden, reaching a possible age of 50 years. Many other proteas tend to become scraggly, taking on an untidy appearance in their old age between 8 and 10 years, but P. aristata retains a very neat shape throughout its long life. To ensure this neat growth, one should take care to regularly prune off all faded flowerheads. P. aristata will thrive in well-drained soil, in a full sun position in the garden provided there are no other encroaching shrubs or plants, so make sure it has plenty of space around it. It performs best in well drained acidic sandstone soils, although it can easily adapt to granitic media providing it is well draining. In the garden it is an excellent specimen for the mixed Fynbos garden, or can be planted in rock garden pockets. Once established, P. aristata proves to be very waterwise. It can be grown in ground in frost-prone areas and handles temperatures as low as -4°C, is frost tolerant and can also be grown well as a container specimen. It will not grow well in wet sites and is even grown at Kirstenbosch National Botanical Garden with some difficulty.
Protea aristata is best propagated from seed. The best time to sow protea seeds is late summer to autumn (March to May in the southern hemisphere) and only plump, fresh seed should be selected for sowing. Many species of Protea have the adaptation of serotiny to survive periodic fynbos fires. Seeds therefore germinate much more successfully after being smoke-treated. Protea seeds are sensitive to excessive amounts of water and are susceptible to rotting, thus it is essential to sow them in a conventional seed tray in a well-aerated, well-drained medium consisting of coarse river sand mixed with finely milled bark (equal ratio). Seeds can be slightly covered with the medium, but make sure not to cover them too much as this will affect germination. If using the tent method of smoke treatment, allow trays to stand in the smoke for two hours and then water the trays to rinse the smoke deposit into the medium. Place treated trays under cover in a shade-house where they will receive optimal fluctuating temperatures of warmer days and cooler nights, between 10°C and 20°C. Prick seedlings out once the first true set of leaves emerge. Plant these into individual pots or containers into the same coarse medium. Water seedlings thoroughly and place under light shade for 7 days to harden off before placing in full sun. Transplant growing plants as required, preventing any unhealthy root formation (Brown et al. 2013).
When cultivated in the artificial garden environment, many species of Protea are susceptible to diseases and pests. Caterpillars, nematodes, scale insects, tipwilters and snout beetles are all possible pests of Protea aristata (Brown et al. 2013). A variety of fungi can cause death of plants. Phytophthora cinnamomi causes root rot and is the most threatening root disease of proteas since it causes heavy losses during warmer summer months.
For more detailed information, refer to Grow proteas in the Kirstenbosch Gardening Series where pests and diseases, as well as their remedies, are discussed in depth.
Acknowledgements: Thanks to Alice Notten who assisted with the writing of this article.
- Duncan, G., Brown, N. & Nurrish, L. 2013. Grow proteas. Kirstenbosch Gardening Series. South African National Biodiversity Institute, Cape Town.
- Daydon Jackson, B. 1979. A glossary of botanic terms. Duckworth, London.
- Jackson, W.P.U. 1990. Origins and meanings of names of South African plant genera . University of Cape Town.
- Rebelo, A.G. 2001. Proteas. A field guide to the proteas of southern Africa, edn 2. Fernwood Press, Vlaeberg, Cape Town.
- Rourke, J.P.1980. The Proteas of Southern Africa by J.P. Rourke. Purnell. Cape Town
- Vogts, M. 1989. South Africa’s Proteaceae. Know them and grow them. Struik Publishers, Cape Town.
Kirstenbosch National Botanical Garde
Plant Type: Shrub
SA Distribution: Western Cape
Soil type: Sandy
Flowering season: Early Summer, Late Summer
Flower colour: Red, Pink
Aspect: Full Sun
Gardening skill: Challenging