WOAD (Isatis tinctoria)
Woad has been used for thousands of years to dye wool and other natural fibres. It is native to Northern Europe and the British Isles. It is closely related to broccoli and cabbage.
Both indigo and woad provide us with a beautiful blue dye. The chemical which gives the blue dye is called indigotin. The indigo plants yields 10 times more indigotin than woad and are therefore much stronger. However it is not generally possible to grow indigo in the British Isles as it requires a hot and humid climate and a long growing period. Although I did once experiment with 100 indigo plants in a forty foot long polytunnel with some measure of success.
Dyeing with woad is more complicated than with other natural dyes – you could say it is in a class of its own!
The benefits of woad are to offer an alternative to the harmful chemicals used in synthetic indigo dyeing.