I love dying fabric! Contrary to my scientific training of precision and reproducibility, I love the serendipitous nature of hand-dying: the lucky chances that place colour on cloth.
Last week I learned how to use indigo - a very different beast from the Procion dyes I had worked with on previously. Indigo doesn't react with fibres, it is insoluble. It has to be altered, chemically, to a soluble (yellow) form which allows it to adsorb onto the surface of the fibres. When it is removed from the dye-bath and exposed to oxygen in the air it converts back to its insoluble blue form.
It's perfect for shibori techniques - once exposed to air, the intense blue dye will not migrate onto other parts of the cloth.
I spent a lot of time tying and stitching cloth to create these lovely patterns, but I think my favourite piece was one that was simply folded, concertina fashion.