ISEND 2011 part 2

The International Symposium & Exhibition on Natural Dyes was held in La Rochelle, France from the 25th to 30th April. The organisers were Dominique Cardon (researcher and author) and Anne de la Sayette (Director CRITT Horticole).

Each day except Wednesday comprised of lectures in the morning followed by a 3 course lunch (with wine) then back to the lectures until 3.30pm. The market place opened at 3.30pm to both delegates and public, the delegates also had the option of attending various workshops and demonstrations until 6.30pm. On Wednesday there were a selection of excursions to choose from in the morning and then back to the lectures for the afternoon. Saturday the market place was open all day plus there were several excursions in the morning.

Lectures tended to be approximately 10 minutes, grouped into sessions, with a small amount of time allocated at the end for discussion and questions.

As I had taken a market stall I was unable to attend the workshops in the afternoon (or the lunches!), however many of them have been videoed and can be found here. Nor did I get the pretty screen printed bag or any of the paperwork, so only my own notes to go from!

I attended the "round table" on indigo with great anticipation, expecting there to be a good chance for discussion and looking forward to hearing the various lectures. The speakers were producers of woad or indigo and it was fascinating to hear their various production methods and their view of how they are taking their product into the future. Woad in particular seems to be looking forward with Woad Inc looking at the health benefits of the oil in the seeds - they have a range of  bath/shower gels, soaps etc. Bleu de Lectoure on the other hand are looking at cosmetics and wood preservatives not to mention the blue corn starch plastics that are being experimented with for recyclable bags, bottles etc. Indigo production in Bangladesh is not a commercial enterprise in terms of specific cultivation - it is grown in any "free" space small areas of uncutivated ground - then collected together and harvested as a co operative. El Salvador have worked out a method of extracting more indigotin and more frequently from their Indigofera suffructiosa and it's organic! Such positive presentations really inspiring!

But what happened to the discussion?

The session leader - when the last speaker had finished - turned to them all and said "do you have any questions for each other?" The main topic was then the "purity" of the product (indigotin) and could it be standardised? What a waste of promising discussion time! When it finally was available to the floor it was very controlled!

Dreadfully done!

The week has left me with my head buzzing and many new contacts and friends made. It is taking a while to assimilate all the information that was available there, some good, some as described above very disappointing. The overall feel of the symposium seemed to be that it was for industrial scale producers rather than artisans, yet those producers were feeling that their audience were the wrong people!

I have to agree with India Flint about the industrial scale production of natural dyes - we are going to have to have a balance between growing food and growing other things - there are already many countries who cannot grow enough food let alone turn their land over to growing dyestuff. In which case we have to collect from the wild and then ...........!

The industrialists were also missing the point that many of the small artisans have had to deal with the same cutivation problems they are going through - and work out a method to get over it, more discussion and less controlling would have been beneficial!

Overall I had a fabulous week and enjoyed it very much, came home absolutely shattered, but  VERY  inspired!

ISEND 2011 part 1

I do believe there have been some Bank Holiday days over the past week and  half - oh and a wedding, but we didn't see any of it/them!!!!

On Easter Saturday we set

off for La Rochelle a 400+ mile journey through beautiful parts of France - Rouen, Le Mans, Angers, we did as little motorway driving as possible - not just to avoid the peage  (we do try to be sensible with our money!!) - but we like to see the scenery! I'm so glad we did on this occasion, we fell in love with the Loir region (just above the Loire) and were surprised by the part of the Charente we saw - so flat! (Photo is of La Fleche, taken on the homeward journey)

La Rochelle is in the Charente Maritime, very pretty in the old town and round the Vieux Port, quite boring round the rest - the landscape was very flat and over all I guess I was disappointed with the area -  so many people told me how lovely it was. As such a popular holiday destination I expected it to have more about it!

We camped! No posh hotel for us, just our trusty van as a bedroom and the Burgundian tent as out living quarters. To be fair it was very comfortable and the Municipal camp site at Port Neuf was fine (certainly not luxurious, but the water was hot enough to shower comfortably!!!) It was a half hour walk to the Vieux Port and about 40 minutes to Espace Encan - the venue for Isend. We walked everywhere, which was lovely, and got to spend time with friends old and new!

I attended ISEND 2011 as a trader only - a decision taken based on the price of attending. I was allowed to attend the lectures during the day, but not the workshops and demonstrations. Set up was on the Sunday, as was registration for all the delegates. I was delighted when Ulrike from the Online Guild came in soon after we'd started and introduced herself, then threw herself into helping with the set up! Thanks Ulrike!

Over the course of the week I got to see many of my old friends from DHA meetings, make contact with my "idols" like Dominique Cardon, Michelle Whipplinger, India Flint .... The biggest thrill of the week was probably talking to Michel Garcia about our water problem here, not long afterwards he appeared at the stall to say he'd take me through and give a demonstration of his indigo vat using sugar as a reducing agent - just me and the lady from El Salvador (whose name I have forgotten I am sorry to say!)  He then gave full details of how the whole thing works, plus the chemistry. All the official delegates had had to scrabble for a bit of space round his demonstration, most unable to hear what he was saying .........

Maybe it wasn't so bad just being there as a trader!

(Part 2 - the conference)

The dreaded subject - Chemistry

When I started writing this blog post I soon realized that it would be very, very long – I have pondered long and hard about whether it should go here or I should try and get it “in print” – it’s not until you start writing that you realize just how complex it all is to explain!!! For this reason I have decided to split the whole thing up into several posts.


For many people indigo is magic but they are simply dyeing with it for the experience rather than wanting to take it further, a simple dye kit or 1 day workshop is great and will satisfy their requirement. For others indigo “bites” and becomes such an integral part of their dyeing repertoire that they really need to understand everything that is happening in the bath and how works. Sadly very few seem to! If you are a professional dyer and particularly if you are writing a book it feels criminal to me that you cannot explain properly how the colour blue is obtained. One of the biggest insults (and reason behind starting all this writing) is when I read (or hear someone say) that it is “normal” for indigo to rub off.

Nooooooooo!

So here I am keeping my promise! I said I would lay my own neck on the line and give what I understand to be the chemistry going on in the “indigo” bath.-

Perhaps I should say here that I have no chemical training further than I took chemistry to A level way back in 1974 and failed it (well got an O level pass, but I already had the O level so......) From then until I took up natural dyeing the only links to the subject that I had were with the nutrition and food poisoning I had to study for my catering qualification. What I am trying to say is that this is a layman’s version, not a chemists!

I would like to start with clarifying names. Everyone talks about dyeing with “Indigo” but that is incorrect, the ACTUAL name of the blue dye chemical is INDIGOTIN (I don’t care how you pronounce it, but that’s how it’s spelt!) So throughout this ramble that is the term I will use when I am talking about the blue dyestuff. ( I feel that we would all get less confused if this term was used more often!)

I am not intending writing here how I use the dye but my understanding of what is chemically happening from the point at which you pick leaves from your chosen source plant and end up with a blue colour on your textile.

When doing a period demonstration dyeing with woad I start by saying::

“There is no blue dye in the leaves,- there is a “precursor” chemical and a naturally occurring chlostridia bacteria in there and when you tear the leaves up into little bits you release the chemical and bacteria into an environment they find suitable for the process of change to begin”

So let’s go through the best known of the plant sources and their “precursors” To clarify what I mean by this - there are many plants which contain a chemical within the leaves that can be converted into indigotin, the plants come from different countries, they are from different family groups and they contain a different chemical but ultimately they can make the required conversion.( I should perhaps also say that different methods of preparation can also be employed for the different plants.)

The Isatis family - Woads

It has not long been known that there is an Isatis family! This is currently under research - there seem to be more varieties than previously thought!

Isatis tinctoria (Woad)

Occurs in a wild state throughout Europe but is thought to originate in Russia. It was not native to England but was cultivated there as it was in Germany and Central Europe. It also can be found in Africa and Asia.

Isatis Tinctoria L. Var. Yezoensis (Ohwi)

 Found in Korea, China and Japan growing wild on hillsides

Isatis Indigotica (Chinese Woad)

This plant has not been found in the wild, only as a cultivated plant.

There are 2 major precursors in Woads – isatan A and isatan B. Indican is also present, but in a very small quantity, so is only a minor precursor for this plant. isatan B and indican are both converted by the same enzymes however isatan A requires a different enzyme. There are other precursors also present but in much smaller quantities and they have yet to be named!

The indigofera family.

This is the most important and largest of indigotin producing families – it is also found in most parts of the world. There are approximately 700 species occurring in sub tropical conditions – so they can be found in the Americas, Asia and Africa. There are no native species in Europe or Australia The ones most commonly known are:

Indigofera tinctoria

 this is sometimes called Indian Indigo Its origins are not known, but are assumed to come from India, although it can be found as far away as South America and Australia

Indigofera .suffruticosa

 Found in Central and South America it has been cultivated in many tropical countries due to its high indican content.

Indigofera arrecta

 Sometimes called Natal Indigo it is native to Africa particularly tropical Africa often at higher altitudes.It was introduced into Java and India.

Indigofera coerulea

 Is found in Sub tropical Africa from Mali to Somalia, also found in Algeria through Arabia to India. This plant was cultivated in the drier area to which it is well suited.

The Indigofera plants all contain the colourless precursor chemical indican in the leaves. The indican content varies from species to species, in the age of the plant, the age of the leaves and even the time of year. For example there is more indican in the young leaves of an older plant that in the young leaves of a young plant, there can also be more in the top leaves of a plant than the bottom! The dye yield from Indigofera arrecta is higher than from any other of the Indigofera species.

Persicaria Tinctoria - Dyers Knotweed

Also known as Polygonum tinctorium it is a native of Vietnam and Southern China. It was introduced in to Japan in the 4th Century AD and became the main source of indigotin.

Again the precursor chemical found in this plants is indican

Around the world there are many more plants which contain precursor chemicals principally indican and they are used by natives of their country. For a more thorough breakdown of all the plants please refer to Natural Dyes by Dominique Cardon her book is by far the best breakdown of what is known at the present time of all the indigotin bearing plants (in my humble opinion!) .

Copyright © Debbie Bamford 25th March 2011