Rhubarb (Rheum spp.)
Rhubarb is not only a great perennial food crop, it can also help to fix dyes produced from other plant sources and create its own dyes. The roots produce shades of yellow and orange; the leaves produce a yellow colour. Harvest the roots for dyeing when dividing a plant. Use chopped roots, either fresh or dried. Leaves can be harvested at any time for use as a mordant for other natural dye materials or to produce their own colour. Rhubarb requires very little effort to grow, as these plants thrive on neglect.