Natural Indigo Dyeing

Natural Indigo is an ancient and fascinating dye, one of the most reliable, colour fast, natural dyes which involves a different way of bonding to fabric than other dye methods.  The process known as vat dyeing involves the use of an activating agent and alkaline which de-oxygenate the vat to make the indigo soluble and bond with the fabric.  It is only when the submerged fabric is removed from the vat and exposed to oxygen again that it changes from a white to a greenish initial colour, gradually developing dark blue.  Watching this happen is a really fascinating and magical part of the process! See me sharing some of the process below from a vat left over from a summer workshop.

Dipping the pre washed and wetted fabric - no mordant is required for indigo dyeing

Removing the greenish fabric after 3 minutes to rinse in a bowl of water

Exposing the green fabric to oxygen again

After 5 minutes the blue colour develops and may continue darkening for up to 20 minutes

 My own experience with creating indigo dye vats has been a bit hit and miss over the years and it’s only recently that I’ve started to feel more confident about the process and managing my vats.  In the recent summer workshop I made up a hydrosulphite vat in a large plastic barrel for my workshop participants to dip their batik work on cotton and silk in.  The blue we achieved was a really lovely deep blue and the vat performed well for the two days of the course and into the week after the workshop still producing deep blues after very short dips of 1-4 minutes.

Darker shades from top on silk and lighter blues on cotton and linen with different shades from the same vat depending on the fabric weave and weight.

I also experimented with boil washing the wax off rather than just ironing and found that the pieces dipped several times held their blue colour well like the long batik piece on the left below.  Those dipped only once faded slightly to a more mid blue colour.

Batik wax resist indigo dipped samples after boil washing drying in the garden

I hope to offer future workshops in batik and indigo dyeing as the two processes work so well together. Do message me and Let me know if it’s something you would like to try!