A wide variety of colours was obtained in this time, using a variety of types of dye. Most of these had to be imported into England, but were readily available on the continent. Merchants and craftsmen specialized in particular dyes.
Woad was a popular dye for blue colours. Since it is not affected by lanolin like many other dyes, it was sometimes used on unprocessed wool, and the resulting fabric was called "blue cloth" in a number of the records (C+C ch. 3), which was generally dyed over again "in the piece", (after weaving), using the blue as a valuable under-tint. Of course woad could also be used to dye in the piece too. Woad was imported to England from Brabant, the Low Countries, Germany, Lombardy and Languedoc.
Yellow was chiefly obtained from a plant called weld, which could be used on its own, or top dyed over woad to make green, or with Madder to make orange and gold. It was cultivated in England, and on the continent.
Reds could be obtained from Madder, using the prepared roots. It was used to obtain an inexpensive red dye, which required a mordant such as alum to affix it to the fibers. The most expensive and sought after dye however was Kermes. It is made from a small Mediterranean insect that, when prepared, looked quite like grain. Hence, dying with it was often called dying "in grain". Items dyed with it are called "scarlet", although the actual colour of the fabric may not look as though any red was involved in its making. Medieval scarlets are often noted as being any number of colours including: green, black, brown, gray, murrey (mulberry), blue, rose, perse and, of course, red! The kermes added a particular brilliance to any of these colours (which could be obtained more cheaply, if more dully, by other means), and its addition (in sufficient proportion) was enough to have them designated with the name "scarlet".