Anemone vesicatoria (L.f.) Prantl (= Knowltonia vesicatoria (L.f.) Sims)
Common names: blisterleaf (Eng.); brandblaar, katjiedrieblaar, tandpynblaar, peperwortel (Afr.)
Anemone vesicatoria is one of the few and best fynbos plants for the shady garden. Tough and water-wise, a mature clump of this plant with its attractive foliage, makes a striking feature under trees.
Anemone vesicatoria is a perennial herb with a tuft of leathery, dark green leaves up to 1.2 m tall. The leaves are divided into three leaflets and attached with leaf stalks to a short horizontal rootstock that is firmly anchored by fleshy roots.
The pretty, small white or yellowish green flowers are borne in clusters just above the foliage, in autumn, winter, spring or early summer.
The flowers are followed by attractive fleshy fruits that turn black as they ripen.
The blisterleaf grows slowly but has a long lifespan, with young plants producing only a few new leaves a year.
Anemone vesicatoria is not threatened, all subspecies are assessed as Least Concern (LC) on the Red List of South African plants.
Distribution and habitat
Anemone vesicatoria occurs widespread within the fynbos of the Western and Eastern Cape, from the Bokkeveld Mountains near Nieuwoudtville, south to the Cape Peninsula and eastwards to Knysna, Port Elizabeth and Grahamstown. It grows in the shade of bushes, in wooded patches, forests, kloofs and river valleys. Variable and adaptable, Anemone vesicatoria is found from sea level to 900 m, in sandy coastal dunes and soil rich in humus. Frost is not common in its natural habitat, but it should be able to withstand light frost with its underground rootstock. Anemone vesicatoria is best suited to areas with a Mediterranean-type climate.
Derivation of name and historical aspects
Anemone vesicatoria was previously known as Knowltonia vesicatoria. The genus Knowltonia was established by Salisbury in 1796 for the southern African species of Ranunculaceae previously placed in the genus Adonis. However, it was soon realised that Knowltonia was more closely allied to Anemone and it was formally included in Anemone by Prantl in 1891. Later South African botanists reinstated Knowltonia as a separate genus, although the differences between them are slight, the main one being that Knowltonia has a fleshy fruit wall whereas it is dry in Anemone. A wide morphological and molecular study of many species in the Ranunculaceae in 1994 concluded that Knowltonia should be included within Anemone, however it was only formally subsumed within Anemone again in 2009. It is now recognized as a lineage of Anemone that has radiated in southern Africa.
Part of the Ranunculaceae family, Anemone includes many popular garden perennials with colourful, cup-shaped flowers. There are 11 species in South Africa. Anemone vesicatoria was the first southern African species of Anemone known to European botanists. l'Obel described it as ‘Ranunculus perelegans D. Franqueville, foliis aculeatis’ in 1655. It is distinguished from the other species by being glabrate (hairless) and by the characteristic teeth of the leaf margin.
Three subspecies of Anemone vesicatoria are recognized:
The subspecies vesicatoria is 200–600 mm, rarely taller than 600 mm, with an erect rhizome with short internodes and light yellow-green flowers in spring (Aug. to Oct.). It grows in humus rich soil in shaded, wooded patches and in moist ravines on the Cape Peninsula to the Bokkeveld to Groot Winterhoek.
The subspecies grossa is a robust plant, 0.6–1.2 m tall, with white to cream to purple flowers at any time of the year, mostly in summer. It occurs in forest and scrub forest in sandy soil on the southern coast from Swellendam to Tsitsikamma. It is geographically separated from subsp. vesicatoria but is commonly cultivated and may have escaped in regions where it did not previously occur.
The subspecies humilis is a small plant, 100–360 mm tall, with a procumbent rhizome with elongated internodes, and light yellow-green to brownish flowers in autumn, winter or spring. Occurs in exposed habitats, in sandy soil, on dunes, in coastal bush and fynbos on the southern coast from Mossel Bay to East London.
The name Anemone comes from a Greek legend where red anemones grew on Mount Olympus from blood shed by Adonis when he was killed by a wild boar. The name is derived from an ancient word, nahamea, meaning ‘handsome’, which is also the meaning of Adonis. The species name vesicatoria is from the Latin vesicare that means ‘to raise blisters’, this refers to the strong allergic reaction caused by the leaves and roots. The common names blisterleaf and brandblaar (meaning burn-leaf) also refers to the allergic skin reaction. The subspecies name grossa means ‘large’ and humilis means ‘low-growing’, referring to their habit. The genus Knowltonia was named after Thomas Knowlton (1691–1781), an eminent English gardener at the botanical garden at Eltham.
Anemone vesicatoria has adapted to survive fire which is part of the fynbos rejuvination cycle, by resprouting from its underground rootstock.
Many species of the Ranunculaceae family contain a toxic irritant oil which has prompted people to experiment with the medicinal uses of the plants. The early settlers at the Cape recognized Anemone vesicatoria as similar to European herbs such as Helleborus and it quickly became a popular herb with numerous uses. One was to use the leaves as a plaster over aching backs and joints. The burning sensation often causing blisters, was considered beneficial for treating arthritis and rheumatism. Colds and flu were treated with a tea made from the roots mixed with Pelargonium roots. Toothache was alleviated by placing a piece of root into the cavity of a decaying tooth.
Anemone vesicatoria is a popular plant for indigenous gardens, but plants are seldom available in the horticultural trade most probably because it grows so slowly.
Growing Anemone vesicatoria
The ripe seeds germinate easily, but the seedlings grow slowly and need patience. Sow the seeds in autumn (March) or as they start to drop from the old flower heads, in a seedtray filled with a well-drained potting mix. Cover the seeds with a thin layer of finely milled bark or sand. Place the seedtray in the shade and water regularly. Grow the young plants on in pots until the rootstock is strong before planting out into the garden; this can take a year or two.
Plant them in the shade and take care to select a special spot where they can establish themselves as a feature over time without strong competition from surrounding groundcovers. Plant it with other shade-loving groundcovers such as Asparagus, Plectranthus, crassulas, gasterias, Streptocarpus ; bulbs such a Ledebouria petiolata (formerly Drimiopsis maculata), Haemanthus albiflos, Scadoxus membranaceus or the small shrub Myrsine africana. The plants respond well to regular watering and a thick application of a compost mulch. Established plants with a strong underground rootstock will be able to survive dry periods.
- Foden, W. & Potter, L. 2005. Anemone vesicatoria (L.f.) Prantl subsp. vesicatoria. National Assessment: Red List of South African Plants version 2020.1. Accessed on 2021/07/09
- Leistner, O.A. (ed.). 2000. Seed plants of southern Africa: families and genera. Strelitzia 10. National Botanical Institute, Pretoria.
- Manning, J.C., Goldblatt, P. & Hoot, S.B. 2009. The genus Knowltonia subsumed within Anemone. Bothalia 39,2: 217–240.
- Pooley, E. 1998. A field guide to wild flowers Kwazulu-Natal and the eastern region. Natal Flora Publications Trust, Durban.
- Rasmussen, H. 1979. The genus Knowltonia (Ranunculaceae). Opera Botanica 53. Stockholm.
- Roberts, M. 1990. Indigenous healing plants. Southern Book Publishers, Halfway House, Johannesburg.
- Smith, C.A. 1966. Common names of South African plants. Memoirs of the Botanical Survey of South Africa No. 35. Government Printer, Pretoria.
- Van Wyk, B.-E. & Gericke, N. 2000. People's plants, a guide to useful plants of southern Africa. Briza Publications, Pretoria.
- van Wyk, B.-E., van Oudtshoorn, B. & Gericke, N. 1997. Medicinal Plants of South Africa. Briza Publications, Pretoria.
Liesl van der Walt
Kirstenbosch National Botanical Garden
Updated by Alice Notten
Kirstenbosch National Botanical Garden
Plant Type: Perennial
SA Distribution: Eastern Cape, Western Cape
Soil type: Sandy, Clay, Loam
Flowering season: Spring, Early Summer, Winter
PH: Acid, Neutral
Flower colour: Green, White, Cream, Yellow
Aspect: Shade, Morning Sun (Semi Shade)
Gardening skill: Average