Serial blue

This weekend I harvested the very last of my indigo leaves for a final extraction. Throughout the season I have dyed for a serial blue.

To learn more about fresh indigo dyeing, pop in at the Dogwood dyer‘s!

This is my first real season of both woad (European and Chinese) and Japanese indigo (Maruba and Kojoko) and it has been such a beautiful experience. I did try both woad and Japanese indigo a few years ago, but the Japanese indigo never germinated and the woad was eaten by flea beetles, so I don’t even count that.

Woad woes

There was some trouble with the woad in the beginning. Our local city fox decided to investigate the pantry properties of the hugelkultur where I had planted my woad. Nighty pantry digging raids resulted in severely damaged plants. Twice. Of the few plants of Chinese woad I had from the beginning I was left with only three. The European woad plants were more from the beginning and I ended up with around eight.

A hand holding three balls of ground and compressed woad leaves. A mortar and pestle in the background.
I made some lovely woad balls out of a whole harvest, but they molded quite quickly.

At one point I harvested all my European woad – over 500 grams – to make woad balls, but they started to mold after just a couple of days. I did a final extraction of the autumn harvest kast week, but it only resulted in a blue tint in the coffee filter. Still, I have lots of seeds left and I am counting on the existing plants to grow another year in the hugelkultur. And oh, they are accompanied by a sweet plant of madder now too.


All through summer I have harvested a small amount of leaves. My first try was a cold water extraction, but the most common method of extraction has been a semi-warm fermentation – 35 °C in the water and a double boiler “thermos” of around 45 °C. The extraction has taken around 18 hours.

When I have decided that the extraction was finished I have removed the leaves and started oxidizing the liquid. This is the most fun part. With just an alkaline addition and some oxygen the liquid turns magically blue and I know I have secured some pigment for future vats.

Baby steps

The reason why my extractions have been so small is practical – my buckets and pots aren’t large enough to ferment the whole harvest in one go. I was a bit annoyed by this in the beginning, but then I realized that multiple extraction for a serial blue has its advantages, at least for me as a beginner. By making small batches I ensure that I can extract some pigment. If one extraction fails I still have the other ones. Had I done it all in one go there would be a risk of it all going down the drain.

A person pouring a blue liquid from a bucket into a pot. In the background are green plants.
Oxidizing my indigo extraction is the most fun part! My small indigo garden to the right.

Another advantage is that I have learned a lot by doing the multiple extractions. I know the signs to look for, I know what the liquid is supposed to smell like and I know how much lime to add in the alkalization stage. I have also created a routine for the extractions that has worked well for my context and my tools.

A small mason jar with a blue liquid in it. The liquid has separated in the top few millimeters.
One of my first Maruba extractions.

After the very last (perhaps tenth all in all?) extraction this week, just before the frost covered the ground in a sparkling blanket, I measured my serial blue dried indigo pigment to around 5 grams. It’s not much, but I have made it all by myself and I am ridiculously proud of every grain of blue.

Fresh leaf dyeing

In the beginning, before I had enough leaves to make extractions, I did some fresh leaf dyeing. I used both the salt rub and the blender method and enjoyed myself tremendously.

As I started extracting I took advantage of the fermented leaves too. The ones that still looked fresh still had some dyeing potential, and I used them with the blender method. Every batch got a small skein of handspun silk and a few linen buttons.

Serial blue

I got some lovely greenish blue skeins in the fresh leaf baths and light blue buttons. However, it was when I started to overdye that the real fun began. By dyeing skeins and buttons two or three times I got a darker and deeper dye from both indigo and woad.

I realized that I could play a lot with this – any skein that ended up too light or unevenly dyed went back into the next bath.

A wooden board with 14 small skeins of handspun silk. They are all in different shades of greenish blue, one is purple. On the ground beneath the board are yellow maple leaves.
Serial blue – multiple dips of my handspun silk yarn in fresh leaf baths.

The colour differs between the two Japanese indigo types and the woad, the Kojoko being a little more vibrant than the Maruba and the woad a little lighter and earthier than the Japanese indigo. On the picture above you can see woad on the fourth from the right. The second and third from the right and the first, second and fifth from the left are Kojoko, the rest is Maruba. The somewhat tousled skeins are dyed with the salt rub method (where the fresh leaves are massaged into the skeins) and the others with the blender method (where the skeins are soaked in leaves that have been blended with ice cold water).


The purple skein is a result of having added some heat and a little alkalinity to already extracted leaves. This can, if you are lucky, bring out the indirubin, which is purple. I did this several times, but this skein was the only one that was worth saving. The second from the left is an overdye from another bath that wasn’t as successful in extracting the indirubin. You can still see some traces of purple in the skein.

Until next year

All the dye pots are stored away now. Of the plants in the garden are just a few stalks left. But on the windowsill in my home office are two pots, one with Kojoko and one with Maruba plants. A few stalks rise high above the others, displaying a multitude of flowers. These are my heroes and seed producers for next year’s dye garden.

A stalk with green leaves and small pink flowers.
Pink flowers on my Maruba plants. The Kojoko flowers are white.

Seeds of Japanese indigo need to be fresh to germinate, so for every season I need to grow new seeds for the next. If I succeed and if the seeds germinate I will have a dye garden of blue in 2024 too, and lots more experience than with this first one.

My play with fresh leaf indio on my handspun silk is over and I do have plans for the skeins. I will also experiment with vat dyeing with the indigo pigment I did manage to extract, which will be a whole new adventure. I’ll keep you posted!

Happy spinning!

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2 Replies to “Serial blue”

  1. So great to read and see this Josefin, thank you so much. You inspire and encourage me and I am so amazed at all you do. I hope to arrange to join patron very soon and also to ask you for another coaching session. I am so enjoying spinning with my spindle. I think I feel confident enough to take another step forward with it and to ask your opinion about the yarn I make. Thank you for all your work and for all you share and teach. It is sustenance and I treasure it.

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