Streptocarpus fanniniae Harv. ex C.B.Clarke
Common names: Cape primrose (Eng.)
Streptocarpus fanniniae is a perennial creeping plant cascading over moist cliffs on streambanks and near waterfalls in KwaZulu-Natal.
Streptocarpus fanniniae is a perennial creeping herb that has a tangle of creeping rooted "stems" up to 150 mm long, and a single big handsome oblong leaf. The lamina (blade of the leaf) is up to 900 x 220 mm, with the margin crenate (scalloped), the base cuneate (wedge-shaped) and with the upper surface and the veins covered thinly with long soft hairs. One or occasionally two inflorescences are borne immediately below the lamina. Many of the flowers open together.
The flowering stalk is up to 300 mm long. The corolla is honey-scented and hairy at the base of the floral tube. The flowers are zygomorphic (symmetrical about only one plane), deeply scented, with the colour varying from almost pure white to blue. The flowering shoots can grow up to 1 m tall. The flowering period is from November to April. The seeds that are produced at the end of the flowering season are minute, usually 0.8-1 mm long, and covered with net-like veins. Streptocarpus fanniniae is a quick-growing plant. It has the ability to spread and cover a big area quickly. It is not known how long the life span of this species is in the wild. Estimates would be in the region of 3 to 5 years.
Streptocarpus is the only genus within the Gesneriaceae family that has a twisted type of fruit.
This species is not threatened and does not qualify for the categories of critically endangered, endangered, vulnerable or near threatened, despite it not being widely distributed.
Distribution and habitat
Streptocarpus fanniniae is restricted to KwaZulu-Natal. It grows in wet habitats with well drained soils, such as the vicinity of waterfalls and stream banks, often in forestry areas. It is found at altitudes between 900 and 1500 m, from Vryheid and Ngome in the north to Ixopo in the south.
Derivation of name and historical aspects
The name Streptocarpus is derived from the Greek streptos = twisted and karpos = fruit. The first Streptocarpus was discovered in 1818 by James Bowie, growing near Knysna. It was identified as Didymocarpus rexii. Ten years later it was realised that the plant belonged in a new genus and was reclassified as Streptocarpus rexii. The Gesneriaceae family is medium-sized containing over a hundred genera, with more than two thousand species.
The Streptocarpus species grow in cool moist habitats; sometimes they are epiphytic (growing on other plants, in this case mostly on trees), but also on rock faces and riverbanks. The seeds are dispersed by wind. S. fanniniae has the ability to wilt severely during unfavourable conditions, thus reducing stress and water loss and afterwards recovering when the conditions become favourable again. This can be classified as an excellent survival strategy.
Streptocarpus species and hybrids are mainly used as indoor pot plants, both locally and overseas. Some of the Streptocarpus species are used as 'muthi' plants for traditional uses within the black culture. The leaf infusions are used to ease birth pains.
Growing Streptocarpus fanniniae
Most of the Streptocarpus species make excellent pot plants and can also be planted in the shady/damp areas of the garden. Place indoor plants in a warm, bright situation, but not in full sun.
Streptocarpus species are attacked by a number of pests and diseases. This can be prevented by using good growing techniques and preventing the plant from being stressed out. Always ensure proper hygiene. Always use sterile potting mix and ensure that all plant containers are sterilized. Do not allow any plant debris to lie about, as this will encourage fungal diseases to develop. Do frequent check-ups on the plants to prevent any problems that may occur at an early stage. Whenever you bring in new plants always check them properly to see if they are healthy enough, before mixing them with the other plants. If you are growing your plants in a glass house, always ensure that it is weed-free. Weeds harbour pests and diseases. To prevent fungal diseases ensure adequate ventilation, avoid excessive sunlight, do not over-water and do not keep plants cold and damp. Always keep an eye open for worms. They love to attack streptocarpuses. When spotted, try to spray immediately with a suitable pesticide.
Feeding should commence in September/October. You can either use a liquid or a granular feed. However it is easier to use a granular fertilizer at the recommended rate. Use a fertilizer that is high in potash. The high potassium will encourage the plant to produce quality flowers rather than leaves.
During winter the leaf turns yellow and then eventually goes brown and dies off. This is a natural reaction to the unfavourable conditions and gives no cause for concern. The new shoots will form from the base again. The dry ends can be removed.
Streptocarpus is best propagated from seed. If a particular hybrid/colour form needs to be kept, then vegetative propagation by cuttings is best suited.
For seed-sowing use a proprietary seed-sowing compost/potting soil. Because the seed is so fine, gently scatter the seed over the surface of the compost. Do not cover the seed with anymore compost. Gently spray with water and cover the seed tray with a sheet of glass or put it in the greenhouse. The trays should be kept at a temperature of about 20°C, in a light place but out of the sun. Always keep the compost damp and never allow it to dry out. The tiny seedlings should be visible around about two to three weeks. Once the seedlings are 5-6 mm long, they can be transplanted into a 100 mm pot.
Streptocarpus can also be propagated from leaf cuttings. The ideal time to do the cuttings is during early spring or early summer. Try and use a well drained soil medium. At the KZN National Botanical Garden we use a mix of 40% potting soil mix, 40% perlite and 20% coarse river sand. The mix must be put into a seed tray. The medium should be sterilized before putting in the cuttings.
The easiest way to take a cutting is to cut off a leaf near the base of the plant and then use this whole leaf as the cutting material. Always take the greenest and healthiest-looking leaf. The leaf should be 100- 150 mm long. You can also cut along either side of the midrib of the leaf to get the cuttings. Use a blade or sharp knife to do the cuttings and ensure that it is sterilized, using a fungicide, to prevent the spread of disease. Once the leaf cuttings are done, insert them 25 mm deep. The cuttings must be put into a bright area but not into full sun. The ideal temperature should be about 20°C.
The cuttings can be placed into a greenhouse or you can cover them with a polythene bag. An elastic band can be used to tie the bag to the tray. The cuttings should take about one month to root. Another two to three weeks later the young plants will appear from the base of the cutting. Always ensure that the medium is kept moist, but not wet. If you want to get more plants growing you can cut the leaf transversely into several pieces. Each piece must be between 50 and 75 mm long. Make sure the centre pieces of the leaf are planted the correct way up. Once the young plants are fully established, between 30 and 50 mm tall, they can be transplanted into slightly bigger pots. The plants can reach the flowering stage within the next two to three months.
Leaf cuttings are one of the best ways of propagating Streptocarpus. However it requires a lot of skill and patience. The more you practice this method, the better your chances are of getting a good take.
- Burtt, B.L. & Hilliard, O.M. 1971. Streptocarpus, an African plant study. University of Natal Press, Pietermaritzburg.
- Dibley, R. 2003. Streptocarpus. Dibleys Nurseries, North Wales.
- Zimmer, G.F. 1912. A popular dictionary of botanical names and terms. Broadway House, London.
- Raimondo, D., Von Staden, L., Foden, W., Victor, J.E., Helme, N.A., Turner, R.C., Kamundi, D.A., Manyama, P.A. (eds) 2009. Red List of South African plants. Strelitzia 25. South African National Biodiversity Institute. Pretoria.
Kwazulu Natal National Botanical Gardens
Plant Type: Perennial
SA Distribution: KwaZulu-Natal
Soil type: Loam
Flowering season: Spring, Early Summer, Late Summer
Flower colour: Blue, White, Mauve/Lilac
Gardening skill: Challenging