Hibiscus cannabinus
| Hibiscus cannabinus | |
| Light: |  |
| Moisture: |  |
| Hardiness: | 10 |
| Soil pH: | 5.6-8.4 |
| Self Pollinated | |
| Height: | 6' |
| Speed: | Fast |
| Blooms: | Late Summer-Early Fall |
| Native to: | |
| Edible Rating: |  |
| Medicinal Rating: |  |
| Tea: | Yes |
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Hibiscus cannabinus (common name: kenaf)
Propagation: Seed - sow early spring in a warm greenhouse. Germination is usually fairly rapid. Prick out the seedlings into individual pots when they are large enough to handle. If growing them as annuals, plant them out into their permanent positions in early summer and protect them with a frame or cloche until they are growing away well. If hoping to grow them as perennials, then it is better to grow them on in the greenhouse for their first year and to plant them out in early summer of the following year.
Cuttings of half-ripe wood, July/August in a frame. Overwinter them in a warm greenhouse and plant out after the last expected frosts.
Cultivation: Prefers a well-drained humus rich fertile soil in full sun[1]. Tolerates most soils but prefers a light sandy soil[2]. Plants are adapted to a wide range of soils and climatic conditions[3]. Kenaf is reported to tolerate an annual precipitation in the range of 57 to 410cm, an annual temperature range of 11.1 to 27.5°C and a pH in the range of 4.3 to 8.2 (though it prefers neutral to slightly acid)[4]. The plant is frost sensitive and damaged by heavy rains with strong winds[4].
Kenaf is widely cultivated in tropical and sub-tropical areas of the world, where it is grown mainly as a fibre crop but also for its seeds and leaves[4]. It is not very hardy outdoors in Britain, it really requires a frost free climate[2]. It can, however, probably be grown as an annual. A fast-growing plant, it can be harvested in 3 - 4 months from seed[5][6]. The plant requires temperatures in the range of 15 - 25°c[7]. It succeeds as a crop as far north in N. America as Indiana, Iowa, Kansas and Nebraska[8].
Plants are daylight sensitive, they remain vegetative and do not flower until the daylength is less than 12.5 hr/day. Two weeks of very cloudy days will induce flowering as daylength approaches 12.5 hr[4].
The plant has a deep-penetrating taproot with deep-seated laterals[4].
Plants, including any varieties, are partially self-fertile[4].
Range: Original habitat is obscure, it probably arose in the tropics of Asia or America.
Habitat: Not known in the wild.
Edibility: Young leaves - cooked[9][10][11]. Used as a potherb or added to soups[12]. The leaves have an acid flavour like sorrel[13].
Seed - roasted or ground into a flour and made into a kind of cake[10][11][12].
Root - it is edible but very fibrousy[14]. Mucilaginous, without very much flavour[14].
An edible oil is obtained from the seed[6][12]. The yield varies from 2 - 10 tonnes per hectare[9] (or is it per acre?).
Medicinal: The juice of the flowers, mixed with sugar and black pepper, is used in the treatment of biliousness with acidity[15].
The seeds are aphrodisiac[15]. They are added to the diet in order to promote weight increase[15]. Externally, they are used as a poultice on pains and bruises[15].
The leaves are purgative[15]. An infusion of the leaves is used in the treatment of coughs[4]. In Ayurvedic medicine, the leaves are used in the treatment of dysentery and bilious, blood and throat disorders.
The powdered leaves are applied to Guinea worms in Africa[4].
The peelings from the stems have been used in the treatment of anaemia, fatigue, lassitude, etc[4].
Usage: Yields a fibre from the stem[16][2], a very good jute substitute though it is a bit coarser[6]. The fibre strands, which are 1.5 - 3 metres long, are used for making rope, cordage, canvas, sacking, carpet backing, nets, table cloths etc[9][2][4]. For the best quality fibre, the stems should be harvested shortly after the flowers open[3][4]. The best fibre is at the base of the stems, so hand pulling is often recommended over machine harvesting[4]. Yields of about 1.25 tonnes of fibre per hectare are average, though 2.7 tonnes has been achieved in Cuba[9][4]. The pulp from the stems has been used in making paper[4].
The seed contains between 18 and 35% of an edible semi-drying oil[6][9]. It is rather similar to groundnut oil, obtained from Arachis hypogaea[15]. The oil is also used for burning, as a lubricant and in making soap, linoleum, paints and varnishes[17][6][9][4]. The seed yield varies from 2 to 10 tonnes per acre[9] (or is it per hectare?).
The stems have been used as plant supports for growing runner beans etc[4].
The soot from the stems has been used as a black pigment in dyes[4].
The stem has been used as a base for drilling fire[4].
Pollinators: Insects
Soil: Can grow in light, medium, and heavy soils.
Drainage: Prefers well drained soil.
Seed Ripens: Mid Fall-Late Fall
Flower Type: Hermaphrodite
Links
References
- ↑ Huxley, Anthony. The New Royal Horticultural Society Dictionary of Gardening. MacMillan Press, 1992.
- ↑ 2.0 2.1 2.2 2.3 Britannica. Encyclopaedia Britannica 15th edition. 1982.
- ↑ 3.0 3.1 Hill, Albert. Economic Botany. The Maple Press, 1952.
- ↑ 4.00 4.01 4.02 4.03 4.04 4.05 4.06 4.07 4.08 4.09 4.10 4.11 4.12 4.13 4.14 4.15 4.16 4.17 Duke, James. Handbook of Energy Crops. 1983.
- ↑ Tutin, Tom et al.. Flora Europaea. Cambridge University Press, 1964.
- ↑ 6.0 6.1 6.2 6.3 6.4 Usher, George. A Dictionary of Plants Used by Man. Constable, 1974.
- ↑ Buchanan, Rita. A Weavers Garden.
- ↑ Natural Food Institute. Wonder Crops 1987.
- ↑ 9.0 9.1 9.2 9.3 9.4 9.5 9.6 Komarov, Vladimir. Flora of the USSR. Gantner Verlag, 1968.
- ↑ 10.0 10.1 Tanaka, Tyōzaburō. Tanaka's Cyclopaedia of Edible Plants of the World. Keigaku Publishing, 1976.
- ↑ 11.0 11.1 Kunkel, Günther. Plants for Human Consumption. Koeltz Scientific Books, 1984.
- ↑ 12.0 12.1 12.2 Facciola, Stephen. Cornucopia - A Source Book of Edible Plants. Kampong Publications, 1990.
- ↑ Hedrick, Ulysses. Sturtevant's Edible Plants of the World. Dover Publications, 1972.
- ↑ 14.0 14.1 Cribb, Alan and Joan Cribb. Wild Food in Australia. Fontana, 1976.
- ↑ 15.0 15.1 15.2 15.3 15.4 15.5 Chopra, R. Glossary of Indian Medicinal Plants. Council of Scientific and Industrial Research, New Delhi, 1986.
- ↑ Chittendon, Fred. RHS Dictionary of Plants. Oxford University Press, 1951.
- ↑ Uphof, Johannes. Dictionary of Economic Plants. Weinheim, 1959.