Iris pseudacorus
Yellow Flag
a perennial member of the Iris genus in the family Iridaceae.
Taxonomy and growth
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.
The leaves, and especially the rhizomes, of this species contain an irritating resinous substance called irisin. If ingested this can cause severe gastric disturbances[15]. Plants can cause skin irritations and allergies in some people[11].
Edible uses
This section contains historical Plants For A Future notes marked noncommercial.
The seed is said to make an excellent coffee substitute as long as it is well roasted[8][18][17][1][2][13]. Caution is advised, it might be poisonous[5].
- Product or use
- Coffee
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.
The fresh root is astringent, cathartic, emetic, emmenagogue and odontalgic[16][18][17]. A slice of the root held against an aching tooth is said to bring immediate relief[13]. It was at one time widely used as a powerful cathartic but is seldom used nowadays because of its extremely acrid nature[16]. It can also cause violent vomiting and diarrhoea[13]. When dried the root loses its acridity and then only acts as an astringent[16].
- Product or use
- Astringent
- Product or use
- Cathartic
- Product or use
- Emetic
- Product or use
- Emmenagogue
- Product or use
- Odontalgic
Material uses
This section contains historical Plants For A Future notes marked noncommercial.
A beautiful yellow dye is obtained from the flowers[16]. A good black dye is obtained from the root if it is mixed with iron sulphate[16][2]. It is brown otherwise[3]. The root is a source of tannin[17] and has been used in making ink[16]. A delicately scented essential oil, obtained from the roots, has been used to adulterate the oil of Acorus calamus[14].
- Product or use
- Dye
- Product or use
- Essential
- Product or use
- Ink
- Product or use
- Tannin
Environment
- Range
- Europe, including Britain, from Norway south and east to N. Africa the Caucasus and W. Asia.
- Habitat
- Damp marshy areas, swampy woods and in shallow water or wet ground on the edges of rivers and ditches[4]. Often found in shady places[16].
- Light
- full sun
- Shade tolerance
- light shade
- Water
- aquatic
- Hardiness
- Zone 5+
- Soil textures
- sandy, loamy
- Soil pH
- acid, neutral, alkaline
- Tolerances
- high wind
- Wind
- Yes
- Tolerates Nutritionally Poor Soil
- No
- Drought
- intolerant
Propagation
This section contains historical Plants For A Future notes marked noncommercial.
Seed - best sown as soon as it is ripe in a cold frame[16]. Stored seed should be sown as early in the year as possible in a cold frame. A period of cold stratification improves germination time and rates. Prick out the seedlings into individual pots when they are large enough to handle and grow them on in the greenhouse or cold frame for their first year. Plant out into their permanent positions in late spring or early summer. Division in March or October. Early autumn is best[9]. 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.
Prefers a humus rich soil[19]. Succeeds in water up to 15cm deep[12]. Requires a moist soil, especially in early summer. Prefers a position in semi-shade[7]. Plants can be grown in quite coarse grass, which can be cut annually in the autumn[10]. A delicately scented essential oil is obtained from the dried roots[14]. Members of this genus are rarely if ever troubled by browsing deer or rabbits[10]. Some named forms have been selected for their ornamental value[6].
References
Tanaka. T. Tanaka's Cyclopaedia of Edible Plants of the World. Keigaku Publishing 1976-00-00
Johnson. C. P. The Useful Plants of Great Britain.
Carruthers. S. P. (Editor) Alternative Enterprises for Agriculture in the UK. Centre for Agricultural Strategy, Univ. of Reading 1986-00-00 ISBN 0704909820
Clapham, Tootin and Warburg. Flora of the British Isles. Cambridge University Press 1962-00-00
Kunkel. G. Plants for Human Consumption. Koeltz Scientific Books 1984-00-00 ISBN 3874292169
Phillips. R. & Rix. M. Perennials Volumes 1 and 2. Pan Books 1991-00-00 ISBN 0-330-30936-9
Brickell. C. The RHS Gardener's Encyclopedia of Plants and Flowers Dorling Kindersley Publishers Ltd. 1990-00-00 ISBN 0-86318-386-7
Hedrick. U. P. Sturtevant's Edible Plants of the World. Dover Publications 1972-00-00 ISBN 0-486-20459-6
Huxley. A. The New RHS Dictionary of Gardening. 1992. MacMillan Press 1992-00-00 ISBN 0-333-47494-5
Thomas. G. S. Perennial Garden Plants J. M. Dent & Sons, London. 1990-00-00 ISBN 0 460 86048 8
Bown. D. Encyclopaedia of Herbs and their Uses. Dorling Kindersley, London. 1995-00-00 ISBN 0-7513-020-31
Baines. C. Making a Wildlife Garden.
Phillips. R. & Foy. N. Herbs Pan Books Ltd. London. 1990-00-00 ISBN 0-330-30725-8
Genders. R. Scented Flora of the World. Robert Hale. London. 1994-00-00 ISBN 0-7090-5440-8
Diggs, Jnr. G.M.; Lipscomb. B. L. & O'Kennon. R. J Illustrated Flora of North Central Texas Botanical Research Institute, Texas. 1999-00-00 http://artemis.austincollege.edu/acad/bio/gdiggs/NCTXpdf.htm
Grieve. A Modern Herbal. Penguin 1984-00-00 ISBN 0-14-046-440-9
Usher. G. A Dictionary of Plants Used by Man. Constable 1974-00-00 ISBN 0094579202
Chiej. R. Encyclopaedia of Medicinal Plants. MacDonald 1984-00-00 ISBN 0-356-10541-5
Innes. C. The World of Iridaceae