Woad

The leaves of this plant are the source of a blue dye, often used instead of indigo. Leaves are collected from flowering stems, dried in the sun, ground into paste and left to ferment. This produces a smell so disgusting that it was an offence in Tudor times to dry woad near the royal palaces.

The fermented leaves are then formed into cakes, mixed with water and fermented again. The colour is drawn out by infusing the woad with lime water. As well as being used for clothing, woad was once used by Celtic warriors to stain their bodies during battle. Some historians think the word Britain came from this custom of war-painting, as the old Celtic for paint was Brith and Brithon meant stained man.