Blue Dye. Indigo is a blue dye that is derived from the leaves of certain plants, including the indigofera and isatis species. You can make blue dye in minecraft by using cornflowers or lapis lazuli.

It may cost a little more than synthetic indigo, but the main cost of handmade items is time. A simple chemical reaction turns the red pigment of beets into a new, nontoxic blue dye.