Glastum Isatis tinctoria

Woad is a herbaceous perennial or biennial plant in the mustard family (Brassicaceae) native to Europe, southwestern Asia and Russia and grows on the steppes and desert zones of these areas. Woad was an important dye-producing plant starting in medieval Europe and was also used as a medicinal plant. It was eventually replaced by indigo.  The Genus name derives from the ancient Greek word for the plant, ἰσάτις. Specific epithet from Latin means used in dyeing.

Woad will grow 2 to 4 feet tall and spread 2 to 3 feet wide. It prefers alkaline to neutral moist well-drained soils with moderate fertility in full sun. It can be propagated by seeds and will self-seed in the landscape. It is a noxious weed in some western states and has experienced aggressive eradication.

The first year, the plant grows as a basal rosette up to 1 foot tall. The second year, a leafy stalk rises above the foliage and produces a raceme of small 4-petaled yellow flowers. These are followed by showy seed pods.

Being from arid areas of the world, it will not do well in the Southeast United States and should not beplanted in western states due to its aggressive nature.

Insects, Diseases, and Other Plant Problems:    No significant problems. Susceptible to club root.