Last year, I tried a cold vinegar process on some indigofera australis. The result was very pale blue, but just the same, blue, especially on silk and linen. I thought this time I’d stick to silk. I also found a direct dyeing method described online and decided to try it out on my indigofera australis.
My friend and I stripped the leaves from the stems and into the blender they went.
Pretty soon we had finely mushed leaves.
I tried both the vinegar method and the direct dye method with no success to speak of, even after repeated dippings.
Remember that the wool on the right of each sample card has been mordanted with rhubarb leaf, so wasn’t white to begin with.
Well, I thought I had nothing to lose by leaving the leaves and the liquid to sit for a few days and trying again, so I reunited the pulverised leaves and the two dye baths.
I thought I’d try hydrosulphite, the last resort in case of indigo failure, in my case. I warmed the liquid and strained out the leaves.
I have recently received a Ph meter as a gift, so I aimed for 10.5 and added washing soda in solution until I reached it. The result was a striking yellow.
However… absolutely no blue whatsoever, not even an improvement on samples I thought I might overdye for improved colour.
Time of harvest? User error in the process? The Ph meter isn’t properly calibrated? The thermometer is out of whack (it certainly didn’t agree with the one on the Ph meter, so I knew one of them must be wrong–and I now know it was the thermometer)? I have no idea, honestly. I’ve decided to leave my one Japanese indigo plant to keep for seed…
Local & Bespoke 
In my limited experience indigofera australis yields a cerulean or turquoise at best. I have a feeling that the recent heavy rains may have affected the plant? You might like to try another means of extracting colour…working with Japanese indigo in Portland last year I found that freezing was a very efficient means of coaxing colour from the leaves…and didn’t have the problem of introducing oxygen by using a blender
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That is a very good point about the oxygen & the blender. I’ve heard of other plants doing interesting things after being frozen, and I wonder what is at action there…
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I’m looking forward to trying it if my Japanese indigo holds out… but I am assuming I can use leaves that have been shredded by hail so far and may yet face frost…
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That’s my experience too–that it is a pale blue source, which seems right given that the concentration of indigotin in the leaves is supposed to be so low. I am never likely to have a crop so large as to produce a deep blue, which is OK with me. The method I was trying to use proposes that air should be introduced by moving the solution from one vessel to another… which I must say I find a bit puzzling given all I have read about the chemistry of indigo–it seems like you introduce oxygen first and then de-oygenate. Odd–but just what Chris (above) clearly does with woad, and with success. It didn’t prevent blue last time… and your point about the rain is an excellent one.
I just read your article in Pip this week, on loan from a friend. Lovely, as always. I have just one Japanese indigo plant and thought I would try your method on whatever leaves remain when I’ve collected seed, and see how I go with that.
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I haven’t worked with indigo, but do dye with woad each year, usually successfully. After introducing the washing soda and whisking to introduce air, I normally sprinkle on Spectralite (Thiourea Dioxide) and leave it to reduce for at least 45 minutes before trying to dye with it. I would imagine that works with indigo as well.
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Yes, it does work with indigo as well, and this is the process I was
usingtrying to use, with colour run remover. I’ll have to check out your posts on woad!LikeLike
a native Australian indigofera? I didn’t realise there was one. it would be very nice to be able to coax some blue out of it.
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Yes, it’s native… and blue certainly can be had from it. Just not this time!
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I’ve done a bit of dyeing with Indigofera Australis today using the direct method. Basically you chop it up, place it in a jar and cover with water. Place an airtight lid on top and keep it warm (next to the fire, heating vent etc.) for 48 hours. This method you avoid introducing oxygen so after the 48 hours you carefully remove leaves and add pre wetted materials for 20 minutes and then remove and let air for 20 minutes. I found after 5 or 6 dips I have some lovely bluey green mid tone colours that I really like. I have seen some really true indigo blue from the australis indigofera but I’m not sure the method used.
I also had no success with hyrdosulphite method. I did a normal dye bath (simmered material with the leaves and all for an hour or so) and go beautiful dusty pinks.
Here is a useful link to the experiments Robyn Heywood has done:
http://www.turkeyredjournal.com/heywood.html
My aim is to one day to obtain that deep indigo colour from Indigofera Australis. I feel like it may be something like making sour dough bread?!
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Thanks, Siri–good to hear that you’re getting good colour from Indigofera Australis. I had success on my first attempt with fresh leaves, using Robyn Heywood’s excellent paper… and then nothing on my second attempt. No doubt due to my own mistakes…! I sometimes wonder if I have enough patience to be a good indigo dyer. But sometimes it just takes a while to develop the capacity to understand and then remember all the processes involved dependably…
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