Woad - Isatis Tinctoria
This wild flower has yellow flowers from June to August. The leaves are harvested when they are mature to produce a blue dye. They grow on grass lands and prefer a sunny spot. The dried seed pods can be used in flower arrangements.
Sow the seed in early spring or late summer. Germination can be improved by soaking the seed in warm water overnight. When you plant the seed do not totally cover. Germination should take about 10 days. Plant out in a sunny, well-drained position. To maximise leaf production for dye, feed and water well.