Edible Parts: Leaves
Edible Uses:

Leaves - they require long soaking in order to remove a bitterness, and even then they are still bitter[177, 179]. There is no record of the seeds being edible, but they contain 12 - 34% protein and 12 - 38% fat on a zero moisture basis[218].

Plants For A Future can not take any responsibility for any adverse effects from the use of plants. Always seek advice from a professional before using a plant medicinally.
Antibacterial  Antiviral  Astringent  Cancer

Woad has rather a mixed press for its medicinal virtues. One author says it is so astringent that it is not fit to be used internally - it is only used externally as a plaster applied to the region of the spleen and as an ointment for ulcers, inflammation and to staunch bleeding[4]. However, it is widely used internally in Chinese herbal medicine where high doses are often employed in order to maintain high levels of active ingredients[238]. The leaves are antibacterial, anticancer, antiviral, astringent and febrifuge[148, 176, 218, 238]. It controls a wide range of pathogenic organisms, including viruses[218, 238]. It is used internally in the treatment of a wide range of disorders, including meningitis, encephalitis, mumps, influenza, erysipelas, heat rash etc[238]. The leaves are harvested in the summer and can be used fresh or dried[238]. They are also macerated and the blue pigment extracted. This is also used medicinally, particularly in the treatment of high fevers and convulsions in children, coughing of blood and as a detoxifier in infections such as mumps[238]. The root is antibacterial and anticancer[176]. It is used in the treatment of fevers, pyogenic inflammation in influenza and meningitis, macula in acute infectious diseases, erysipelas, mumps and epidemic parotitis[176]. Its antibacterial action is effective against Bacillus subtilis, haemolytic streptococcus,, C. diphtheriae, E. coli, Bacillus typhi, B. paratyphi, Shigella dysenteriae, S. flexneri and Salmonella enteritidis[176]. Both the leaves and the roots are used in the treatment of pneumonia[218]. The root and the whole plant have anticancer properties whilst extracts of the plant have shown bactericidal properties[218].

Dye  Preservative

Woad is historically famous as a dye plant, having been used as a body paint by the ancient Britons prior to the invasion of the Romans[238]. A blue dye is obtained from the leaves by a complex process that involves fermenting the leaves and produces a foul stench[6, 14, 46, 57, 100, 238]. The dye is rarely used nowadays, having been replaced first by the tropical Indigofera tinctoria and more recently by synthetic substitutes[238]. Nevertheless, it is a very good quality dye that still finds some use amongst artists etc who want to work with natural dyes. A very good quality green is obtained by mixing it with Dyer's greenwood (Genista tinctoria)[238]. Woad is also used to improve the colour and quality of indigo, as well as to form a base for black dyes[244]. The leaves are harvested when fully grown and 3 - 4 harvests can be made in total[244]. Recent research in Germany has shown that (the dyestuff in?) this plant is a very good preservative for wood[Radio 4 Farming programme].

Special Uses