"The three plants form the basis for primary colors. They were often combined to make other shades like green, orange, purple ...

They might, however, plant beds every year ... There are two colors extracted from madder, when boiled, a red and a dingy yellow : but when the red alone is required the liquoi must be kept ...

Blue, yellow and red were three of the main colours of the Iron Age. The root of the madder plant produced a red colour, woad offered blue and yellow was derived from weld. Plants were soaked in ...