Isatis tinctoria, also called woad, dyer's woad, or glastum, is a flowering plant in the family Brassicaceae with a documented history of use as a blue dye and medicinal plant. It is occasionally known as Asp of Jerusalem. Woad is also the name of a blue dye produced from the leaves of the plant.
Sow Outside: Cover seed. Late summer. Spacing 6 to 12 inches (15 to 30 cm).
Sow Inside: Germination time: two weeks to two months. Temperature: 10°C. Seven or eight weeks in advance. Transplant outdoors before the last frost.
Requirements and care: Full sunlight or partial shade. Good drainage. Rich soil. Propagate: Self seeds.
Miscellaneous: Was used by the Celts to produce blue war paint. Considered an invasive weed in many areas. Used in traditional Chinese medicine in the treatment of the flu, measles and scarlet fever, amongst others.