Japanese Indigo August 2017

Way back in August I ran a Japanese indigo vat. Here’s what the bed of Japanese indigo plants looked like on August 20th:

I have only dyed with fresh Japanese indigo leaves a few times, so I am still trying to develop skill with the process. An important part of developing skill is repetition. Another important piece is learning and testing new things, and then trying to understand why they do or don’t work. Luckily, this vat afforded me all of those opportunities!

I picked 22 oz. of plant material, which yielded exactly 1 pound (16 oz.) of leaves trimmed off of the stems. Here are the tips of the plant stalks that I harvested:

On the left are the stems, and on the right is the bag with just the leaves in it. It’s a really beautiful plant! It has sweet little hairs, wrapped-around layers, exciting color contrasts, and an interesting juxtaposition of rigid and luscious textures.

I wanted to over-dye six small skeins (about two ounces each) of pale blue cotton yarns (commercial 10/2). They had all previously been dyed with woad, and several of them had gone through other processes, too. Two had been dyed in an umbilicate lichen vat, but had only become vaguely pinkish beige in that process. Five had been soaked in a gallotannin solution in an attempt to achieve a teal or blue-green color with woad. One had been in a weld exhaust bath after several dips in a woad vat. All the skeins were still disappointingly pale. I find cotton very difficult to dye!

I used the canning jar “double boiler” method again for this vat. I’ve described this process before, but I figured it was worth repeating here.

I crammed the leaves into half gallon and quart jars, filled them to the shoulder with cold tap water, and put the lid on. I set the jars inside a pot with water about three quarters of the way up the height of the jar.

Here’s all the equipment and the way the jars were arranged in the pots:

I slowly heated the pots of water over the course of two hours. One of the pots accidentally got up to 180º for the last fifteen minutes, but I was aiming for 160º. Here’s what the liquid in the jar looked like after two hours. On the left is the top of the jar and on the right is the liquid in the bottom of the jar:

This is what the leaves looked like when I opened the jars. The metallic sheen that you can see on the right is always a good sign!

Once I strained out the leaves, I had about two gallons of liquid. I used ammonia to get the pH up to 9:

The color changes dramatically with the pH shift. This is true with woad, too. But in my experience, Japanese indigo and woad don’t act or look the same way. On the left below is the greenish color that came out of the jars. Usually, extracted woad is pink or red. On the right is the way it looked after I added a lot of ammonia. The liquid is completely opaque, but now it looks sort of red. Usually with woad, the liquid turns dark green after I add the ammonia.

In this case, the photo on the left is before I added ammonia, and the photo on the right is after:

Then I aerated the liquid for about 10 minutes by pouring the liquid back and forth between different buckets. I had set the timer for ten minutes, but my back started hurting.

I decided to use thiourea dioxide for the reducing agent. I usually use Rit Color Remover, which contains sodium hydrosulfite. But, I had some thiox left over from an indigo vat in the spring, and I have heard it has a short shelf-life. I followed the recommendations from Rita Buchanan in A Weaver’s Garden of 1 Tbsp thiox or 2 Tbs. sodium hydrosulfite per gallon of liquid.

After 50 minutes, the vat didn’t really look reduced, but I stuck in a skein anyway. Usually I look for a murky greenish yellow, but I was kind of impatient!

When you dip fiber into a woad or indigo vat that has been chemically reduced, the reducing agent also functions as a color-stripper. So, if there is color on the skein already, you have to be careful not to let it sit in the vat too long. If you leave it in too long, the original color will be stripped off. On the other hand, I have found that the “quick dips” that are recommended for indigo vats using powdered indigo don’t work for me when I’m using a vat with fresh leaves. So, I left the first skein in for ten minutes.

That worked fine. I put the second skein in for ten minutes, then bumped the pH back up (it had gone down to 8) with a little more ammonia. The third and fourth skeins were in for 20 minutes, the 5th skein was in for 30 minutes, and the last skein was in for about an hour and a half.

While the skeins were oxidizing but still wet, the color was very promising!

While I was getting ready for this vat, I re-read my notes from a dyeing workshop with Joan Morris at Long Ridge Farm. I noticed that she recommended neutralizing cellulose fiber with tannic acid rather than acetic acid (vinegar) after a vat. Since the pH of a vat is very high, you are supposed to neutralize the fibers by soaking them in a mild acidic solution afterwards. I always do this with wool, since protein fibers are damaged with a high pH. Somehow I had forgotten that this was also important with cellulose fibers. And I had completely missed the tannic acid recommendation. So, I thought I’d better look into it.

A little bit of poking around on line led me to Catherine Ellis’ blog Natural Dye: Experiments and Results. What a fabulous resource! I found this post about over-dying with indigo especially interesting.

I had two kinds of tannins at that moment (not including black tea–my favorite is Barry’s gold blend, which I would rather drink than use for dyeing!). I decided to use Earthhues gallotannin, which is very light.

I always wait until the fiber is completely dry, if I can, before rinsing, so it took a couple days to get to the neutralizing and rinsing stage. I dissolved 1 tsp. of gallotannin in about 2 gallons of water (a dishpan) to soak all the cotton skeins before rinsing. The pH was between 7-8. That seemed weird for something called tannic “acid”. In case you need a refresher on your pH scale, 7 is considered neutral, and anything below that is considered acidic. Anything above 7 is considered alkaline. Adding an acid to water ought to make an acidic solution. Or so I thought.

I tested the pH of the plain, hot tap water. I got a surprising pH 8-9. What? I was shocked. I checked around, and apparently it is not unusual for the pH of tap water to be this high. So much for the notion that water is “neutral”.

Soaking in the not-acidic pH solution with tannic acid didn’t help much. A lot of color rinsed out from the cotton skeins. Perhaps I should have made a stronger solution with tannic acid. I was reluctant to make it too strong, though, because tannins can also shift the color to a duller or browner tone. I didn’t want the blues to get muddy.

I did a second soak and rinse with laundry detergent in hot water, but color was still rinsing off. So, I made a new solution with acetic acid (white vinegar) to make a mildly acidic bath of pH 6, and soaked all the skeins in that. It seemed to do the trick.

I clearly need to do more reading about why tannic acid is better for cellulose fibers. Meanwhile, the dried skeins are a *bit* but not a *lot* darker than before. I am not sure it is worth it to me to continue banging my head against cotton yarns.



My new book cloth is a variation of a miniature overshot motif called Hopvine. To create my threading I worked from two other drafts. One was “Modified Hopvine” from a sampler from the Hill Institute. The other was “Modified Hop Vine” from Marguerite Davison’s classic A Handweaver’s Pattern Book. The threading from Hill had too many ends in each pattern repeat to suit the scale of my book covers (5.5 inches by 8 inches) so I wanted to make the motif smaller. The Davison draft had fewer ends in a repeat but looked weirdly jittery in the drawdown in my weaving software.

So, I tinkered until I found a satisfying balance in the pattern, and am still tinkering with the treadling. The design consists of two different diamonds, one a longer and more pointed and the other a little more squat and rounded. I am not sure if these are supposed to evoke different elements of a hop vine, for example the leaves and the inflorescences. Or maybe the name of the pattern has a different origin. There are some nice images of hops plants here.

For those of you who recall my emboldening tabby travails of a year ago, you might be surprised to hear that I ran into the same problem of keeping a consistent tabby this time, also. Sigh. Continue reading “Hopvine”

Recent Books

Back in September, I finished a custom order of 8 books, which was very satisfying. I used only naturally-dyed pattern weft, in linen, cottolin, and cotton (the warp and tabby wefts were commercial). I had a variety of weld-dyed yellow, madder-dyed pink and terra-cotta, and woad-dyed blue yarns to work with. They were all woven in an overshot pattern called Young Lovers Knot, which I have been using for my book cloth for about a year now.

You may recall my frustration earlier in the spring when I was weaving the cloth, and I was bored of weaving the same pattern over and over again. I complained about it at the time, and then got re-inspired when I bought some new tabby weft colors. I also switched from weaving the design star fashion, which creates boxes and distinct diagonal lines as you weave, to weaving rose fashion, which makes the motifs rounded and gives a sense of concentric circles rippling outward. Continue reading “Recent Books”

Another Woad Vat

Yesterday I picked 8 and a half pounds of woad leaves. This is a lot, probably the largest quantity I’ve harvested at one time. Many of the leaves are droopy and yellow at this point in the summer. It has been hot and dry, but there is a lot of color in them, so no worries.

woad in AugustI had written earlier in the summer about woad’s enemies. To fend off the cabbage whites, I planted two hyssop plants, which are supposed to help. I could only find anise hyssop, which may or may not be the right type. It definitely attracts the adult butterflies, as a food source I suspect. But I’m not sure it keeps them from laying eggs on the woad, and it’s the caterpillars that eat the woad leaves, not the butterflies.

anise hyssopI think at this point in the summer that slugs are the main predator on the woad, but I did find quite a few cabbage white eggs. The hyssop is very pretty, though, and it smells great, and the woad is doing OK, so even if the cabbage whites are still laying eggs on it, I guess it’s all fine. Continue reading “Another Woad Vat”

Dishtowels for Pioneer Valley Weavers’ Guild

I am a member of two local weaving guilds, Pioneer Valley Weavers’ Guild and Weavers of Western Massachusetts. The Pioneer Valley Weavers did a community service project this year where members wove dishtowels to donate to the Big Brothers Big Sisters fundraising auctions this summer and fall.

I decided to use Ms and Os for my weave structure, to get some nice bumpy texture. Here are my dishtowels in process. Here is the warp threaded, sleyed, tied on, and ready to go:

Ms and Os dishtowel warpIt is a mixture of different sizes of cotton yarns, as I was trying to use old yarns from my stash. So, the black is 6/2, the light green and gold are 10/2, and the cream is 8/2. I think they are all mercerized, but they are still soft enough to be absorbent. The width is 22.3 inches in the reed, and it’s 536 ends sett at 24 epi, sleyed 2 per dent in a 12 dent reed. I wound a 4 yard warp, which I thought would be enough for three full sized towels. As it turned out, I only had enough for two towels and one smaller napkin or bread-basket sized cloth.

One towel has a pale yellow 22/2 cottolin weft:

pale yellow cottolin weftI like this one because the values and proportions in the stripes work the way I imagined, and I like the lacy feeling.

I wove the other towel with a bright turquoise blue 6/2 cotton weft:

turquoise blue weftThe intensity/saturation of the turquoise interferes with the stripes. As Matthew put it, everything feels like it’s underwater. In future, to use this color weft again, I would redesign the stripes in a smaller scale and with different colors. I think that a more intense bright yellow would work better than the gold, for example. On the other hand, several people to whom I showed the finished towels said they preferred the turquoise one.

For the smaller napkin-sized piece, I alternated the turquoise and pale yellow, and I like the plaid effect a lot (the pale green stripe at the bottom is plain weave, which I sewed into the hem).

turquoise and pale yellow stripesstriped napkinAbove, the napkin-sized cloth looks round because it’s draped over a round foot stool, but I think you can see the plaid effect pretty well.



Microscope Images of Flax Fibers

On Thursday, May 17th, our flax and linen study group met at the lab of one of our members to look at flax fibers under a microscope (and cotton and wool, for comparison). It was so incredibly fun!

Here are the tools and equipment we used to make slides.

making slides (permanent mount)We used tweezers to position our samples and to pull them apart a little to separate the fibers so the light could pass through. We put our samples on a slide (in the square boxes on the right), and added a drop of the mounting adhesive on top (from the little bottle in the blue box). Then we dropped on a small glass cover and used tweezers to press out the air bubbles and get the adhesive to spread evenly between the slide and the cover (small glass covers are in the orange box).  Sharpies are for labeling slides. The pink yarn in back is madder-dyed 40/2 linen. Scissors and razor blades are for cutting. Because the samples were dry, we could make permanent mounts.

Folks brought in a range of flax in various stages of processing: dried but un-retted, retted but unbroken, and retted and broken but not scutched (or hetcheled), and fully processed strick, both old and recent. We looked at flax in several different stages including some of my naturally dyed yarn.

Here is the microscope.

microscopeHere’s the big monitor, which was awesome because we could all see the slides without having to take turns looking through the microscope.

monitorThe program let us do things like adjust the color and take photographs.

We took a lot of very beautiful photos. Here are a few highlights. This image shows the tips of two flax cells overlapping. You can see it in the upper-most edge of the large central bundle, just to the right of the less-in-focus strand that’s crossing diagonally in the left hand corner. Those two greyish-colored pointy tips are the ends of two fiber cells.

retted and broken flax cell ends overlapThe granular purplish area just to the right of the overlapping cell ends shows that part of the structure of the fiber there is hollow. The black circles are air bubbles. Beautiful but irrelevant.

This image shows cotton fibers for comparison. Cotton fibers are flat and ribbon-like in structure, and they twist, whereas flax fibers are rounded or tubular.

cotton 2There is some twist in the structure of flax fibers, also. The image below shows this twisting (in a greenish color in the thin strand in the center). One important thing I learned on Thursday is that the flax fibers we use for spinning and weaving are not the fibers from the circulatory system of the plant (xylem and phloem), which I had previously believed. In fact, they are the structures that give the plant strength and rigidity. They are associated with the vascular cells but are different.

retted and broken flax twistThe two images below show strick fibers (fully processed and ready to spin) from the Zinzendorf brothers in Pennsylvania. The flax was grown and processed on their farm. In the top photo, the center-most green, translucent strand shows the horizontal bars that are typical of flax fibers. In the upper left hand corner you can also see some brown decayed plant matter that is still sticking to the fibers. Click on the images to see a larger view.

brother johannes strickbrother johannes strick 2On slide below we used a stain that shows lignin (the woody material that makes the fibers strong and rigid) in blue and pectin (the starchy glue that holds cells together) in pink. This is a piece of water-retted flax fiber. In the process of water retting, bacteria consume the pectins and allow the fibers inside the plant stalk to separate from the woody core and the outside “skin” of the stalk. If you let the retting continue until all the pectins are eaten, then the individual cells separate also, and you don’t get long fibers to spin. You just get a hairy mess. So, since these fibers are still holding together, there is still pectin present. We think the blue made the pink hard to see. You can see the tubular structure of the flax fibers and the horizontal bars very clearly.

stained retted flaxThe photos below show pale pink madder-dyed 40/2 linen. I used alum acetate for the mordant. I was amazed at how the color sticks to the fibers in clumps. I wonder if yarns with a darker color would show the color adhering more evenly.

madder dyed linen yarn1This photo shows some strands of undyed fiber next to the dyed fibers. I wonder if these were on the inside of the yarn and came free when I teased apart the snippet of yarn to put on the slide.

undyed strandWho knows what is going on here, but whatever it is, it doesn’t look good. That little nugget of color is about to get away.

madder clumpHopefully we will have a chance in future to look at cross sections of the plant stalks at different points in their growth, to see how the fiber bundles develop. Science is fun!



Exhausted Madder and Exhausted with my Warp

I have exhausted the madder bath I’ve been working on.

madder exhaust on bleached cottonThese are the 10/2 bleached cotton skeins which were double-mordanted with aluminum acetate and heated in the calcium carbonate fixing solution. Actually, I could probably run one more bath for an extremely pale pink, but I’m ready to move on with other projects.

Now that I have a pretty decent stash of naturally dyed cotton, linen, and cottolin, I have been using only naturally dyed pattern weft yarns for my current batch of book cloth (the warp and tabby yarns are commercial). Thus far, I have really enjoyed using yarns that I dyed myself. However, on Monday I was having a mightily difficult time choosing color combinations. I couldn’t figure out what my problem was, but I was dissatisfied with everything I tried.  Colors that I had been perfectly happy with before–my screaming yellow weld, for example–looked ugly and annoying.

After a while I realized that I was just tired of weaving the same pattern over and over again (Young Lovers Knot). I put on enough warp for about 20 pieces, with the idea that I was being efficient. But instead I was bored. I am never, ever bored. There is so much to do all the time, and so many interesting things in the world, how could I ever be bored? It took me a while to recognize the feeling, and I felt better when I figured it out.

So, I decided to mix things up a little. I bought some new spring-like colors of 20/2 cotton (the sadly discontinued line from UKI) and decided to use commercially dyed 10/2 for the pattern weft for a while. I also switched from weaving the Young Lovers Knot pattern “Star Fashion” (which gives it those nice diagonal lines) to weaving it “Rose Fashion” (which makes all the motifs more rounded). It was a nice change of pace, and the new colors got me motivated again. In fact, with the new tabby colors, my naturally dyed yarns have taken on all sorts of new possibilities. Here is a 20/2 linen madder-dyed skein from the recent dyebath woven with a rich purple commercially dyed 20/2 cotton tabby weft. It’s sort of easter-eggy but considering that crocuses, daffodils, and all the other bulbs are blooming now, it feels OK to me.

madder-dyed pattern weft with purple tabby

Madder Exhaust with Bleached Cotton

I decided to let the twice-mordanted bleached 10/2 cotton skeins air out until the vinegar smell was extremely faint, but not the full 4 to 7 days that Liles recommends. They dried from Thursday morning until Saturday morning, then I used a fixing solution. I used half an ounce of calcium carbonate, which suspends in the water more than dissolves, really. I didn’t use dung. I stirred it up with very hot water, added the dry skeins, put the pot on the stove, and heated up to about 150 degrees, stirring periodically, for 30 minutes.

Here are the extremely white skeins in the milky white fixing solution:

fixing solution with bleached cottonIt almost looks like I’ve dyed the skeins white. After 30 minutes, I pulled out the skeins and rinsed them twice, then I had to go to work so I left them to soak in plain water. In the evening I rinsed them twice again.

As it turned out, the fine, moldy-looking film which had been growing on the surface of the madder dyebath got displaced by increasingly large bubbles from fermentation (I assume–not sure about the microbiology here). The dyebath was a bit slimy but none the worse for wear, and it didn’t even smell too bad.

I know I said that I wasn’t going to try anything new this time around except for the scouring and mordanting steps, but I did try two other things. Liles suggests soaking the goods in the dyebath for at least half an hour before applying any heat, and then heating for at least 2 hours. He writes that alizarin, the main red-producing dyestuff in madder roots, is not very soluble in cold water, and just a little more so in hot water. Starting out cold, raising the temperature slowly, and heating for a prolonged period of time (Liles recommends up to 3 hours for cotton) allows the fiber to take up the alizarin as it slowly dissolves. I did soak the bleached cotton skeins before heating. I soaked the first two for 30 minutes, and the third for about 6 hours. Each has soaked overnight in the dyebath before drying and then rinsing. I will post a photo when they are all done.


I Do Detect the Smell of Acetic Acid

I have mordanted my bleached 10/2 cotton skeins a second time with aluminum acetate, which involved heating at 100 for an hour (it actually got up to 150 at one point, oops), cooling overnight in the mordant bath, and hanging outside to dry this morning. This afternoon they are not yet dry, but they do have a strong vinegar-like smell which I think must be the acetic acid Liles mentioned. So I gather I ought to wait until that smell dissipates, which could be several days, before I dye the yarn. Meanwhile, my madder bath is starting to get moldy. I have a pretty high tolerance for decomposition and stinky things, but in a few more days it will be yucky. What to do?

Madder Dyed Yarns

After a leisurely process of heating, soaking, and delayed rinse, the first four skeins of madder-dyed yarns are done. Here they are outside today, a bright and sunny day.

madder dyed yarnsI’ve done four dyebaths so far. The photo above shows successive dyebaths moving from right to left. The yarn on the cone is from the first dyebath. The yarns in the first three dyebaths were 20/2 linen and the fourth was 22/2 cottolin. The linen yarns were mordanted with alum acetate, and the cottolin was mordanted with alum acetate plus tannin. The weight of goods in each dyebath was about 2 ounces.

For the last couple exhaust baths I am preparing 10/2 cotton (bleached) because that’s what I have on hand at the moment. After some disappointing results with my last two umbilicate dyebaths, and out of a general desire to achieve greater depth and brightness of colors on cellulose fibers, I am going to try some new procedures. I’m especially frustrated with cotton at the moment, and for help I am turning to Jim Liles’ book The Art and Craft of Natural Dyeing: Traditional Recipes for Modern Use. In his instructions for scouring cotton, Liles writes, “… simmer or boil for an absolute minimum of 2 hours. Three or 4 hours is better in some cases, and in the old days cotton was sometimes scoured at the boil for 8 hours. Cotton is full of wax, pectic substances, and oil, all of which must be removed.” This is much longer than I’ve ever scoured before.

So, I boiled the skeins for two hours with anionic scour (from Earthues) and soda ash. Then I rinsed them three times, and mordanted with alum acetate at 5% weight of the goods at 100 degrees for one hour, let the yarns steep in the mordant for a couple days, dried them, and am now re-mordanting in the same mordant bath. This procedure is a combination of my usual cellulose treatments (based on recommendations from Earthues) and recommendations from Jim Liles.

Double-mordanting with a period of drying in between is a new experiment for me. Liles gives instructions for making your own aluminum acetate, and writes that you should wait until the acetic acid smell has dissipated before proceeding with dyeing. Since I am using alum acetate that I did not have to make myself, I didn’t detect any acetic acid smell after mordanting the first time, so I went ahead with the second mordant bath after just drying the skeins for a day.

Next will come the “fixing solution” Liles recommends. To remove unbonded mordant, he recommends soaking with a solution of calcium carbonate or sodium phosphate for 30 minutes, then rinsing with water. I’m not sure from the book whether I can just use calcium carbonate, or whether it has to be soaked with cattle or sheep dung. It seems to me that if I have the calcium carbonate, I don’t need the dung (since that seems to be a source of sodium and calcium phosphate), but maybe it helps.

Since I am already pretty far along with this madder project, I’m not planning to make any changes to my usual dyeing, drying, or rinsing steps with the last exhaust baths this time around.

However, for my next madder project I will try one of Liles’ recipes for madder red. Reading through his recipes has been very eye-opening and I am fascinated by, and kind of surprised by, many of the things he writes about. For example, instead of just rinsing the madder-dyed goods, he describes a process where the dyed material is simmered or boiled with soap. This is supposed to make the color brighter and more clear. I watch the temperature very carefully while the roots are extracting and the yarn is in the dyebath to make sure it *doesn’t* boil or even simmer. It never occurred to me that high heat later in the process could be beneficial. Also, he writes that the dyebath ought to be acidic when dyeing cotton or linen with madder. Oops. Did you see my pH comments in the last post? Clearly I had the wrong idea about what that calcium carbonate was for. In fact, he writes that making the dyebath alkaline will produce a bluish-purple. Well, I didn’t get anything like purple this time with my alkaline dyebath, but maybe I can…. So many things to try.

Here’s the madder-dyed linen yarn getting woven into cloth with black 20/2 cotton tabby weft.

cloth with madder-dyed yarn coming around the breast beamThis shot is from underneath the breastbeam to show the cloth winding onto the cloth beam. I really like these colors together. The blue-green is woad overdyed with weld.

book cloth going onto cloth beam