Woad- from the dye garden to the dye pot
In the first lockdown for the first time I had the opportunity to grow a mini dye garden from seeds. Being a complete novice I didn’t expect too much. I watched most of the seeds turning into seedlings and that was the beginning of something very exciting. Here the woad plant is about a year old and has been flowering the last month or so, it is about a meter tall.
Woad is a biennial plant which forms leaves in the first year then flowers and goes into seeds the next year. The first year leaves yield best the blue pigment.
To extract the blue pigment it is preferable to use the leaves fresh. Here they come straight from the garden. The recipe follows one of the method Jenny Dean describes in her book ‘Wild Colour’.
The leaves are firstly removed from their stem, then washed and cut into small pieces. There is about 350 g of woad leaves here. Boiling water is poured onto the leaves and left to stand for an hour.
The leaves are then drained and kept for a second batch if needed. The dye liquid has a pinky colour. When the dye is about 50 degrees we add a small spoon of Soda Ash to it. This makes the liquid turn green. We now need to give air to the dye liquid by whisking it or by pouring it from one recipient to another. This creates a blue froth. The froth needs to subside before we can go to the next step. To speed up the process I skim some of the froth and put it aside.
Now we can reheat the dye liquid to 50 degrees. Not having a thermometer handy, it is more a guess than an accuracy! When the temperature reaches 50 degrees we sprinkle a couple of teaspoons of spectralite to the dye bath and let it stand for 45 minutes.
Spectralite (Thiourea Dioxide) is a replacement for Sodium Hydrosulphite and is an active reducing agent which removes the oxygen from woad when combined with Soda Ash.
After 45 minutes the colour blue of the liquid turns yellow-green. We heat it up again and keep it on a low temperature of 50 degrees. The woad dye bath is now ready to receive some fabric!
There is no need to mordant the fabric beforehand. The fabric has been washed and just soaked in water before adding it to the dye bath. It is important to immerse the fabric entirely as it will get blotchy otherwise. In this example the fabric sticks slightly outside the dye bath and turns blue in the oxygen.
The fabric is left in the dye bath at 50 degrees with a lid on for 20 minutes. When removing the fabric from the dye bath the fabric turns from yellow to blue in the oxygen. It is then plunge briefly in a bucket of water which should prevent/remove any blotching. Finally the fabric is hanged to air for about 20 minutes before the process of dyeing is repeated 1 to 3 more times. This, to build up desired colour.
Dyeing with woad on different fabrics result in a variety of the colour blue-turquoise.
There are others methods of extracting and dyeing with woad but none are quick and easy processes I understand. One that doesn’t use any chemical would be ideal.
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