Indigo dye can be extracted from a variety of plants in different parts of the world and different kinds of natural environment. In fact, there are over 800 species of indigo-bearing plants found throughout the world.
Within the project, we mainly focus on the cultivation and use of Persicaria tinctoria, a plant from the buckwheat family (also known as Dyer’s Knotweed or Japanese Indigo) that is native to Eastern Europe and Asia. There are different varieties of Persicaria tinctoria including Kojōko with white flowers and pointed leaves and Senbon with pink flowers and rounded leaves. The leaves of Persicaria tinctoria have a high concentration of indigo and as we believe that this species is best suited to the harsh climate of the Waldviertel region of northern Austria, we are giving it a hundred square meters of space to grow.
In addition, we cultivate woad (Isatis tinctoria), which used to be the main source of indigo in the temperate zones of Europe but generally yields smaller amounts of blue dye, as well as other indigo species with a higher indigo content, such as West African Indigofera arrecta and Central American Indigofera suffructicosa for experimental purposes.