Isatis tinctoria 'Dyer's Woad'

[Olbia, Sardinia, Italy]

Brassicaceae: a hardy biennial or short-lived perennial 60cm. Found cliffs and cornfields, often on chalky soils. Numerous small yellow flowers are borne in branched panicles. Blooming from May – July. The flowers are followed by pendent, fiddle-shaped, black seed. It has a stout taproot, erect stems and oblong-lanceolate grey-green leaves. Native to Central and Southern Europe. Naturalized in Southern England.

USES:

The leaves can be eaten but they require long soaking to remove a bitterness, and even then, they are still bitter.

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. However, it is widely used internally in Chinese herbal medicine where high doses are often employed to maintain high levels of active ingredients. The leaves have antibacterial, anticancer, antiviral, astringent and febrifuge properties.

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. A blue dye is obtained from the leaves by a complex process that involves fermenting the leaves and produces a foul stench.

GROWING INFORMATION:

Rapidly germinating, keep seed in constant moisture (not wet) with temperatures of about +20°C [68°F]. Seeds must be covered thinly. Do not cover very small seeds, but tightly press into the earth. Keep in cooler conditions after germination occurs. An easily grown plant, it prefers a well-drained fertile soil in a sunny position, though it succeeds in ordinary garden soil. Plants deplete the soil of nutrients and cannot be grown successfully on the same site for more than two years. Plants self-sow freely when they are grown in a suitable position.

HARVESTED: 2023*