More from the natural dyeing course at Ditchling Museum of Art and Craft

This session was the last for substantive dyes and we used alkanet root, pomegranate peel and cutch (all without a mordant), with the usual four modifiers.

Although substantive dyes will fix without a mordant, the use of an aluminium mordant often gives different results because the alum attracts other pigments which may be present, particularly the flavonoids or yellow pigments. So cutch used with an alum mordant tends to give yellower shades than cutch used without a mordant and with an alum mordant walnut leaves often give yellows but they give tans and browns if used without a mordant. Be aware, too, that using an alum mordant will not necessarily improve fastness. In tests conducted by Gill Dalby, walnut leaves used on an alum mordant had lower fastness than walnut leaves used without a mordant.

This time I tried a different method with the alkanet root, which I soaked in vodka for 3 days before the workshop. This is because the red pigment in alkanet root is not soluble in water but should be soluble in neat alcohol. I have tried rubbing alcohol but I found that the slight improvement in colour in no way compensated for the unpleasant fumes of the dye bath. I had read that vodka might be a useful alternative, so I decided to try that.The vodka was then used as part of the dye bath, with water added. This might seem like a rather unsuitable use of vodka but it was the best alternative I could find. In fact, I wouldn’t waste good vodka again, as the difference in colour, compared with the results without vodka, was negligible.

Alkanet root (Photo by Zuzana Krskova)