Read here about Yellow Flag Iris, Iris pseudacorus, its medicinal uses and place in folklore.
This plant, known commonly as Yellow Flag, is one of two irises** native to the UK, though there are many other wild species and dozens of garden cultivars. The Yellow Flag is a common and cheerful sight lining the banks of canals and slow-moving rivers, and it propagates either by underwater rhizomes or from the seeds that fill the large three-sided seed pods – the seeds float readily and so may spread along waterways to found new sites. The flower is made up of three short inner petals and three large outer ‘tepals’ which have striking reddish markings. This form is unique in British wild flowers.
Medicinal Uses and Properties
Culpeper, the 17th century herbalist, called the plant Flower-de-Luce or Yellow Water-Flag. He stated: “The root is of a very astringent, cooling and drying nature“ which he suggested would help diarrhoea and excessive bleeding. He also said “The distilled water of the whole herb, flowers and roots, is a sovereign remedy for weak eyes…”
Other herbalists suggest:
Toothache may be eased by holding a piece of fresh root against the tooth
Mixing the juice from the crushed roots with wine makes a strong purgative
The juice is also useful as a cosmetic treatment to remove freckles
WARNING: Nowadays it is not recommended to ingest any part of the plant, which produces an irritating resinous substance called irisin. Violent vomiting and diarrhoea are likely effects.
(Orris Root, which is used in homeopathic medicine, is not derived from our native plant, but from other iris species. It is also commercially used in perfumery, potpourri etc.)
Other Uses
As a dye plant: yellow from the flowers; green or yellow from the leaves, the different colours obtained by using different mordants (fixatives); and brown from the root, or black if mixed with iron sulphate.
Yellow Flag is a useful plant for waste purification in wetlands and managed reedbeds, as it absorbs nutrient pollutants such as agricultural run off.
Myth and Magic
Named for the rainbow goddess Iris, from ancient times the plant was a symbol of power. The Egyptians placed it on the royal sceptre, the three parts of its blossom representing faith, wisdom and valour. The Romans dedicated the plant to Juno and called it consecratix, as they used it for purifications. It is an Iris that is represented by the symbol Fleur-de-Lis / Lys, even though that name often translates as Lily Flower. In Celtic mythology, the Gaelic names of the plant usually have the meaning ‘plant of light’, and that is another interpretation of Fleur-de-Lis.
**The other native Iris is Iris foetidissima, or Stinking Iris, so called because to some people it smells meaty or unpleasant when crushed. It has dull bluish flowers and is only found in England south of Durham and in Ireland in open woodland, in hedgebanks and on sea cliffs, but is widespread in much of Europe.
Acknowledgements thanks to the following for some of this information:
Culpeper’s Complete Herbal
www.pfaf.org (Plants for A Future)
www.rhs.org.uk
