Artemisia annua

Taxonomy and growth

Family

Compositae

Genus

Artemisia

Life cycle

annual

Growth rate

vigorous

Height

3 m

Spread

1 m

Fertility

Insects

Flower type

hermaphrodite

Pollinators

Insects

Uses

Edible uses

This section contains historical Plants For A Future notes marked noncommercial.

An essential oil in the leaves is used as a flavouring in spirits such as vermouth^[13].

Medicinal uses

Historical medicinal uses. These records describe reported uses. They do not establish safety or effectiveness. Ask a qualified health professional before using any plant medicinally.

This section contains historical Plants For A Future notes marked noncommercial.

Qing Ho, better known in the West as sweet wormwood, is a traditional Chinese herbal medicine. An aromatic anti-bacterial plant, recent research has shown that it destroys malarial parasites, lowers fevers and checks bleeding^[9][12][14]. It is often used in the Tropics as an affordable and effective anti-malarial^[12]. The leaves are antiperiodic, antiseptic, digestive, febrifuge^[2][3]. An infusion of the leaves is used internally to treat fevers, colds, diarrhoea etc^[6][12]. Externally, the leaves are poulticed onto nose bleeds, boils and abscesses^[6][9]. The leaves are harvested in the summer, before the plant comes into flower, and are dried for later use^[12]. The plant contains artemisinin, this substance has proved to be a dramatically effective anti-malarial against multi-drug resistant Plasmodium spp^{[5][9][12][13]}. Clinical trials have shown it to be 90% effective and more successful than standard drugs^[12]. In a trial of 2000 patients, all were cured of the disease^[5]. The seeds are used in the treatment of flatulence, indigestion and night sweats^[6].

Material uses

This section contains historical Plants For A Future notes marked noncommercial.

The plant is used in China as a medium for growing Aspergillus which is used in brewing wine. The substances mentioned above in the medicinal uses, used in the treatment of malaria, also show marked herbicidal activity^[6]. The plant yields 0.3% essential oil^[10]. This has an agreeable, refreshing and slightly balsamic odour and has been used in perfumery^[10].

Environment

Range

S. E. Europe to W. Asia.

Habitat

Occurs naturally as part of a steppe vegetation in the northern parts of Chahar and Suiyuan provinces in China, at 1000 to 1500 m above sea level^[13].

Light

full sun

Shade tolerance

light shade

Water

moderate

Hardiness

Zone 7+

Soil textures

sandy, loamy

Soil pH

acid, neutral, alkaline

Drainage

well drained

Tolerates Nutritionally Poor Soil

No

Drought

intolerant

Propagation

This section contains historical Plants For A Future notes marked noncommercial.

Cultivation

This section contains historical Plants For A Future notes marked noncommercial.

An easily grown plant, succeeding in a well-drained circumneutral or slightly alkaline loamy soil, preferring a sunny position^[1][4]. Plants are longer lived, more hardy and more aromatic when they are grown in a poor dry soil^[11]. A fast-growing annual plant, it is tall but neat in habit with a handsome fragrant foliage and is useful for filling gaps at the back of a border^[9]. It has become a weed of waste places in many areas of the world^[15]. The plant is extremely vigorous and essentially disease and pest free^[13]. Qing Hao is a determinate short-day plant. Non-juvenile plants are very responsive to photoperiodic stimulus and flower about two weeks after induction. The critical photoperiod seems to be about 13.5 hours, but there are likely to be photoperiod x temperature interactions. In Lafayette Indiana, USA (40°21'N) plants flower in early September with mature seeds produced in October. The plant is not adapted to the tropics because flowering will be induced when the plants are very small^[13]. Most collections of artemisia derive from natural stands with highly variable artemisinin content, some as low of 0.01%. Selections from Chinese origin vary from 0.05 to 0.21%. Swiss researcher N. Delabays reports a clonal selection derived from Chinese material which produces 1.1% artemisin but is very late flowering; proprietary hybrids have been obtained with somewhat lower content but flower earlier^[13]. Members of this genus are rarely if ever troubled by browsing deer^[7].

Related plants

• Artemisia abrotanumSouthernwood
• Artemisia absinthumWormwood
• Artemisia anomala
• Artemisia argyi

References

1. F. Chittendon. RHS Dictionary of Plants plus Supplement. 1956 Oxford University Press 1951-00-00

   ↩

2. Yeung. Him-Che. Handbook of Chinese Herbs and Formulas. Institute of Chinese Medicine, Los Angeles 1985-00-00

   ↩

3. Stuart. Rev. G. A. Chinese Materia Medica. Taipei. Southern Materials Centre

   ↩

4. Huxley. A. The New RHS Dictionary of Gardening. 1992. MacMillan Press 1992-00-00 ISBN 0-333-47494-5

   ↩

5. Duke. J. A. and Ayensu. E. S. Medicinal Plants of China Reference Publications, Inc. 1985-00-00 ISBN 0-917256-20-4

   ↩1↩2

6. Foster. S. & Duke. J. A. A Field Guide to Medicinal Plants. Eastern and Central N. America. Houghton Mifflin Co. 1990-00-00 ISBN 0395467225

   ↩1↩2↩3↩4↩5

7. Thomas. G. S. Perennial Garden Plants J. M. Dent & Sons, London. 1990-00-00 ISBN 0 460 86048 8

   ↩

8. Britton. N. L. Brown. A. An Illustrated Flora of the Northern United States and Canada Dover Publications. New York. 1970-00-00 ISBN 0-486-22642-5

9. Bown. D. Encyclopaedia of Herbs and their Uses. Dorling Kindersley, London. 1995-00-00 ISBN 0-7513-020-31

   ↩1↩2↩3↩4

10. Chopra. R. N., Nayar. S. L. and Chopra. I. C. Glossary of Indian Medicinal Plants (Including the Supplement). Council of Scientific and Industrial Research, New Delhi. 1986-00-00

    ↩1↩2

11. Genders. R. Scented Flora of the World. Robert Hale. London. 1994-00-00 ISBN 0-7090-5440-8

    ↩

12. Chevallier. A. The Encyclopedia of Medicinal Plants Dorling Kindersley. London 1996-00-00 ISBN 9-780751-303148

    ↩1↩2↩3↩4↩5↩6

13. Duke. J. Handbook of Energy Crops - 1983-00-00

    ↩1↩2↩3↩4↩5↩6↩7

14. Medicinal Plants in the Republic of Korea World Health Organisation, Manila 1998-00-00 ISBN 92 9061 120 0

    ↩

15. Fernald. M. L. Gray's Manual of Botany. American Book Co. 1950-00-00

    ↩