Practical
Plants

Hypericum perforatum

St. John's Wort

a perennial member of the Hypericum genus in the family Hypericaceae.

No photo available

Taxonomy and growth

Life cycle
perennial
Height
0.9 m
Spread
0.6 m
Fertility
Self fertile, Bees, Flies, Self
Flower type
hermaphrodite
Pollinators
Bees, Flies, Self

Uses

Toxicity

Toxicity warning. The historical record reports a hazard for this plant. Do not use it to decide which parts are safe to eat or use medicinally.

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

Skin contact with the sap, or ingestion of the plant, can cause photosensitivity in some people[4][27][13].

Edible uses

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

The herb and the fruit are sometimes used as a tea substitute[25][9]. The flowers can be used in making mead[9].

Product or use
Tea

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.

St. John's wort has a long history of herbal use. It fell out of favour in the nineteenth century but recent research has brought it back to prominence as an extremely valuable remedy for nervous problems[20]. In clinical trials about 67% of patients with mild to moderate depression improved when taking this plant[20]. The flowers and leaves are analgesic, antiseptic, antispasmodic, aromatic, astringent, cholagogue, digestive, diuretic, expectorant, nervine, resolvent, sedative, stimulant, vermifuge and vulnerary[23][28][4][11][6][12][13]. The herb is used in treating a wide range of disorders, including pulmonary complaints, bladder problems, diarrhoea and nervous depression[23]. It is also very effectual in treating overnight incontinence of urine in children[23]. Externally, it is used in poultices to dispel herd tumours, caked breasts, bruising etc[23]. The flowering shoots are harvested in early summer and dried for later use[25]. Use the plant with caution and do not prescribe it for patients with chronic depression[16]. The plant was used to procure an abortion by some native North Americans, so it is best not used by pregnant women[21]. See also the notes above on toxicity[11][13]. A tea or tincture of the fresh flowers is a popular treatment for external ulcers, burns, wounds (especially those with severed nerve tissue), sores, bruises, cramps etc[13][16]. An infusion of the flowers in olive oil is applied externally to wounds, sores, ulcers, swellings, rheumatism etc[18]. It is also valued in the treatment of sunburn and as a cosmetic preparation to the skin[18]. The plant contains many biologically active compounds including rutin, pectin, choline, sitosterol, hypericin and pseudohypericin[13]. These last two compounds have been shown to have potent anti-retroviral activity without serious side effects and they are being researched in the treatment of AIDS[13][16]. A homeopathic remedy is made from the fresh whole flowering plant[15]. It is used in the treatment of injuries, bites, stings etc and is said to be the first remedy to consider when nerve-rich areas such as the spine, eyes, fingers etc are injured[15].

Product or use
Analgesic
Product or use
Antiseptic
Product or use
Antispasmodic
Product or use
Aromatic
Product or use
Astringent
Product or use
Cholagogue
Product or use
Digestive
Product or use
Diuretic
Product or use
Expectorant
Product or use
Homeopathy
Product or use
Nervine
Product or use
Resolvent
Product or use
Sedative
Product or use
Stimulant
Product or use
Vermifuge
Product or use
Vulnerary

Material uses

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

Yellow, gold and brown dyes are obtained from the flowers and leaves[7]. A red is obtained from the flowers after acidification[5]. A red dye is obtained from the whole plant when infused in oil or alcohol[25][24][3]. A yellow is obtained when it is infused in water[25][26][3]. The plant is said to contain good quantities of tannin, though exact figures are not available[14].

Product or use
Dye
Product or use
Tannin

Environment

Range
Europe, including Britain, south and east to N. Africa, the Azores, Madeira and W. Asia.
Habitat
Open woods, hedgebanks and grassland, in dry sunny places, usually on calcareous soils[25][8].
Light
full sun
Shade tolerance
light shade
Water
moderate
Hardiness
Zone 3+
Soil textures
sandy, loamy, clay
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.

Seed - sow in a greenhouse as soon as it is ripe in the autumn or in the spring. It normally germinates in 1 - 3 months at 10°c. Prick out the seedlings into individual pots when they are large enough to handle and plant them out into their permanent positions in the summer. Division in spring or autumn[2][16]. Very easy, larger clumps can be replanted direct into their permanent positions, though it is best to pot up smaller clumps and grow them on in a cold frame until they are rooting well. Plant them out in the spring.

Cultivation

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

Easily grown in any reasonably good well-drained but moisture retentive soil[1]. Succeeds in dry soils[16]. Plants grow well in sun or semi-shade but they flower better when in a sunny position[10]. St. John's wort is often found as a weed in the garden[1]. It grows well in the summer meadow and is a useful plant for attracting insects[17]. The whole plant, especially when in bloom, gives off a most unpleasant smell when handled[19]. Hypericum perforatum is apparently an allotetraploid that would appear to have arisen from a cross between two diploid taxa, viz. H. maculatum subsp. maculatum (Europe to western Siberia) and H. attenuatum (western Siberia to China)[22].

References

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

    ↩1↩2

  2. Sanders. T. W. Popular Hardy Perennials. Collingridge 1926-00-00

    ↩

  3. Johnson. C. P. The Useful Plants of Great Britain.

    ↩1↩2

  4. Triska. Dr. Hamlyn Encyclopaedia of Plants. Hamlyn 1975-00-00 ISBN 0-600-33545-3

    ↩1↩2

  5. Carruthers. S. P. (Editor) Alternative Enterprises for Agriculture in the UK. Centre for Agricultural Strategy, Univ. of Reading 1986-00-00 ISBN 0704909820

    ↩

  6. Mills. S. Y. The Dictionary of Modern Herbalism.

    ↩

  7. Grae. I. Nature's Colors - Dyes from Plants. MacMillan Publishing Co. New York. 1974-00-00 ISBN 0-02-544950-8

    ↩

  8. Clapham, Tootin and Warburg. Flora of the British Isles. Cambridge University Press 1962-00-00

    ↩

  9. Facciola. S. Cornucopia - A Source Book of Edible Plants. Kampong Publications 1990-00-00 ISBN 0-9628087-0-9

    ↩1↩2

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

    ↩

  11. Lust. J. The Herb Book. Bantam books 1983-00-00 ISBN 0-553-23827-2

    ↩1↩2

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

    ↩

  13. 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↩6

  14. Rottsieper. E.H.W. Vegetable Tannins The Forestal Land, Timber and Railways Co. Ltd. 1946-00-00

    ↩

  15. Castro. M. The Complete Homeopathy Handbook. Macmillan. London. 1990-00-00 ISBN 0-333-55581-3

    ↩1↩2

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

    ↩1↩2↩3↩4↩5

  17. Baines. C. Making a Wildlife Garden.

    ↩

  18. 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

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

    ↩

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

    ↩1↩2

  21. Moerman. D. Native American Ethnobotany Timber Press. Oregon. 1998-00-00 ISBN 0-88192-453-9

    ↩

  22. Flora of China 1994-00-00 http://flora.huh.harvard.edu/china/

    ↩

  23. Grieve. A Modern Herbal. Penguin 1984-00-00 ISBN 0-14-046-440-9

    ↩1↩2↩3↩4

  24. Usher. G. A Dictionary of Plants Used by Man. Constable 1974-00-00 ISBN 0094579202

    ↩

  25. Chiej. R. Encyclopaedia of Medicinal Plants. MacDonald 1984-00-00 ISBN 0-356-10541-5

    ↩1↩2↩3↩4↩5

  26. Komarov. V. L. Flora of the USSR. Israel Program for Scientific Translation 1968-00-00

    ↩

  27. Cooper. M. and Johnson. A. Poisonous Plants in Britain and their Effects on Animals and Man. HMSO 1984-00-00 ISBN 0112425291

    ↩

  28. Launert. E. Edible and Medicinal Plants. Hamlyn 1981-00-00 ISBN 0-600-37216-2

    ↩

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