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Catherine Ellis - 5-day Natural Dye Workshop, Berkeley

DyeHaus had the absolute pleasure to attend a 5 day immersion extravaganza of Natural Dyeing in Berkeley in September 2019, held by Catherine Ellis.

The objective was to look at important aspects of Natural Dyeing one topic per day.

This format was very successful, as it allowed for a low stress experience and the ability to focus on just one aspect of a very complex topic at a time.

The course complemented Catherine and Joy Boutrup’s recently published book ‘The Art and Science of Natural Dyes’, a title that sums its contents up very well.

The two authors, a textile scientist and dyer of several decades, have compiled a work that will set a new standard for dyers the world over.

In addition it focuses on ease of use, availability of ingredients and low cost practices.

In my opinion the books that have been published in recent years, relied on old research, but here every statement is backed up by tests!

The dyeworld needed a new guideline, as with the proliferation of interest in Natural Dyes, the amount of speculation and misinformation has grown accordingly.

As a tutor Catherine is very generous in sharing her wisdom, she is patient and the wonderful smile did not left her face during the entire week. Not an easy feat with a class of dyers who threw a barrage of questions at her all day, for 5 days.

The workshop was extremely well prepared, with lots of well labeled and relevant examples. She did a lot of tests and they all worked wonderfully and illustrated the point made.

Although I have read the book, I am so glad I made the effort to go and study with Catherine in person as it has clarified many aspects, made me rethink my practice and given inspiration for further private research. Not to mention the opportunity to make new friends and grow our dyerswww.

I will start with the first two topics and will continue soon with the other 3 days once I have unpacked my studio and can access my notebook!

Day 1.

Exploring tannins for mordanting and dyeing

TANNINS are a very important topic as they INCREASE LIGHTFASTNESS so we want to use them as much as possible.

However we still have to mordant, even if a dye contains tannins. (Of course there is an exception but not now...)

There are different types of tannins with varying properties.

GALLIC tannin like GALLNUT is preferred as it is colourless and strong.

ELLAGIC tannins like MYROBALAN and POMEGRANATE are strong and also can be used as a dye in their own right.

The addition of a weak iron bath increases the light fastness even more, but also saddens the colours.

Left above:

Immersion dyeing with various tannins such as Chestnut, Cutch, Myrobalan, Pomegranate, Quebracho and Blackwattle adding alum and iron

Right above:

Weld with various tannins and additional iron solution


Tannins such as Chestnut, Cutch, Myrobalan, Pomegranate, Quebracho and Blackwattle with 1. added alum and 2. added iron

Day 2.

Dyeing Proteins without Mordants

One bath acid method

So what is the one bath acid method and why do we use it? When is it appropriate?

What is in the one bath acid dye bath?

  • dye

  • vinegar (not citric acid)

  • tannin (more on tannins later)

  • Simmer on low heat for 1 hr

Why do we use it?

  • to save time on mordanting

When is it appropriate?

The one bath method

  • does not work for all dyes. It is particularly successful with the RED DYES like ALKANET, COCHINEAL, MADDER, LAC as well as pomegranate and walnut

  • Wool is the best substrate for this process. It will work on silk, but not as effectively.

This is a comparison of one bath method and mordanting for cellulose and protein separately

The top row was done in Rhubarb

the bottom in Madder

but all are composed of a mixture of cellulose and protein fibre

The different dye absorption is clearly visible. The top right has been done in Acid one bath method, The other two samples have been mordanted for cotton and cellulose,

They are a wonderful example of Crossdyeing.


On a fabric that is composed of a mixture of cellulose and protein fibres, you can achieve very interesting effects as each fibre has a different uptake of the one dye. This is of particular interest to the WEAVERS amongst you. As you can determine the fibre composition.

Samples of one bath acid method on wool, giving very saturated colours,

From left to right:

Rhubarb, Madder, Lac, Alkanet

Certainly a very interesting technique, a great timesaver where appropriate.

More to follow



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