Woad leaf

The Woad leaf is a blue leaf that is used to make blue dye, and by extension green dye and purple dye. Players must take two woad leaves and five coins to Aggie to make blue dye ; this is enough to dye one item.

Members can grow woad leaves at level 25 Farming by planting a woad seed in a flower patch. Alternatively, players can buy woad leaves from Wyson the gardener in Falador Park. Offering him 20 coins provides the best value, since he actually gives two for being so generous.

Woad leaves play a part in Goblin Diplomacy, since they are required for making dye used on goblin mail during the quest.

Trivia
In real-life medieval Europe (which RuneScape takes some inspiration from), woad was indeed used to make blue dye. However, blue would have been an expensive colour, and was the "royal" colour of France.