Friday, 25 May 2018

Dyeing Wool with Birch and Plum Tree Leaves using Alum Mordant at Various Concentrations

Not long ago, I accidentally mordanted some Shetland wool yarn using 20% of the weight of the wool in alum crystals, instead of my usual 10%. I thought the amount of colour the yarn picked up from a dye bath of birch tree leaves looked far more impressive than the colour on a smaller skein of the same yarn that had been dyed in the same bath after being mordanted with 10% alum. 


Over a cup of tea in the garden, my companion, Elinor Gotland, quite agreed.
"The little skein looks crap compared to the big one with more mordant. Looks like you've been spoiling the ship for a ha'porth of tar, Beaut. Speaking of ha'porths, how much does alum actually cost?"
"Well, very little actually. I paid about £12 for a kilogram, so even if I didn't reuse the solution, the difference between using 10g or 20g of alum to mordant 100g of wool would be 12 pence. I'm not so fussed about the money, so much as the environmental cost of using more."
"Oh, for heaven's sake, aluminium is the most abundant metal on earth and you're always harping on about how you exhaust your mordant solutions by reusing them three times. Do yourself a favour and get the best out of those plant dye baths you spend half your life brewing up. Making mouldy colours is a waste of all the natural gas you burn, simmering dye pots for hours on end."
"Hmmm. Maybe you've got a point, Elinor. I've read older dye recipes where higher percentages of alum seem to have been standard practice. Along with Glauber's Salts and a whole range of other stuff you don't see in the chemists' anymore. Perhaps the old girls had the right idea all along."

My accidental 20% alum mordant bath included some 50g skeins of Drops Alaska aran wool yarn. I mordanted a couple more skeins with 15% alum and 10% alum and then collected another 150g birch tree leaves while out walking the dog. After simmering the leaves for an hour, I added an equal weight of yarn and half a teaspoon of soda ash to bring the pH just above neutral, simmered the wool in the pot for an hour and left it to soak overnight.


Once the yarn had dried, there wasn't much difference between the three skeins. They were all more yellow and less green than the previous birch leaf dye, which may be because the leaves are no longer so very newly grown. The skeins were tagged, so I knew the one on the left of this picture was mordanted with 10% alum and could see it was only very marginally yellower in tone and slightly paler than the one on the right, which had been mordanted with 20% alum. This made it clear that I hadn't managed to replicate the conditions which produced the contrast between the original 20% versus 10% mordanted skeins. Above and beyond that, it made no sense to me that the skein in the middle, which had been mordanted with 15% alum, looked paler than either of the others.


Obviously, first thing to do was to repeat the test. No flowers are anywhere near blooming in the dye garden, but the plum trees espaliered against the wall needed their tips soft pruned this week. I used to get yellow dyes from the leaves of the apple trees that grew there before, so this seemed a good opportunity to test the dye potential of my plum tree leaves as well as repeating the alum mordant assessment.

150g fresh plum tree leaves were simmered in water for an hour. They released no perceptible colour into the dye bath and its pH tested as mildly acidic. I put three skeins of yarn into the clear fluid, although I only had 25g mordanted with 10% alum, and simmered them for an hour. Next morning, they looked pale yellowish green. When I rinsed them in plain water the yellow grew stronger as the acidic dye bath was washed out, so I gave them a final soak with half a teaspoon of dissolved soda ash. The alkali turned them a proper lemon, paler and sharper than the colour from birch leaves.


No two ways about it, the mordant results were essentially the same, only more pronounced. The 10% skein on the left of the picture is only marginally paler than the 20% skein on the right, while the 15% skein in the middle is paler than either of them.

"From the looks of that wool, you might as well carry on mordanting with 10% alum, Beaut. Don't bother increasing to 20%, save your 12p and spend it on a teabag." My companion gazed sorrowfully into her empty teacup. "I know it's wildly extravagant of me to expect a second cup of tea to have any colour in it."
"A second cup? Your teapot must hold the Welsh record for continuous use. It doesn't go cold all day."
The unsatisfactory tea concentration provided by Elinor's reused teabag did set me thinking. Does reusing an alum mordant bath really have just as good an effect as the first use? Could that original small pale skein have resulted from mordanting the wool in a reused alum bath? On reflection, I remembered that the 15% alum skeins of wool were mordanted cold, whereas both the 20% and the 10% alum skeins were mordanted by heating. These days, I often mordant wool without heat. It does seem to work, but I've never directly compared the dye results after mordanting wool by simmering in alum for an hour against the dye results on wool mordanted by soaking in a cold alum solution for 24 hours.  Maybe cold mordanting is why the 15% skeins came out so pale. Maybe in the original birch leaf dye bath, the little 10% alum skein was mordanted cold in a reused bath of alum.


No good speculating, I think I am going to need to do another trial to try to get clear on this point before the dye garden comes into flower. Still a few weeks to go yet.

Friday, 18 May 2018

Hammered Leaf Prints Made Fast with Iron Solution

Every May when the trees come into leaf, I find myself full of enthusiasm for their loveliness and inclined to start collecting some for hammer printing. Then I work away on a piece of cloth and soon remember hammering is a noisy business that rapidly grows dull and find I've chosen the soft, squashy kinds of leaves which get mashed into the fabric or dryer ones that barely leave a mark, no matter how I thump them. A lot of trial and error gets repeated every year for transient rewards, having found from past experience that the pretty fresh green hammer leaf prints will fade to pale beige within a few months of exposure to light. 


This year, I was encouraged to experiment again after checking my friend's curtains. Last year, I hammer printed leaf borders for them on mordanted fabric, then dyed the fabric in a bath of meadowsweet flowers with added iron, which turned the prints into brown silhouettes. Rather to my surprise, they haven't faded despite the sun shining through them all year, the curtains look much the same as when we hung them up last May. It seems to me that the leaf juices must have been able to pick up and concentrate the iron that was in the dye bath, as I know iron is a particularly lightfast mordant for plant dyes. This year's experiment was intended to find out whether it is necessary to premordant the cotton fabric in order to make iron hammerprints permanent.

First I mordanted one piece of cotton curtain fabric by simmering it for an hour in a solution of aluminium acetate at 5% the weight of the fabric. Then I made a dye bath by simmering 100g of silver birch leaves in water with a teaspoon of soda ash to increase the pH. Next, I collected leaves and wedged a board on a garden wall to provide a solid surface for hammering.
Using an old shirt to lay over the leaves, which were laid reverse side down on my curtain fabric, I thumped away until the juices had soaked through the shirt showing a complete leaf shape, lifted away the shirt then peeled off the leaves. After that, I did much the same to two more pieces of the same fabric which hadn't been mordanted.



One of the unmordanted pieces was just heated in water with a splash of dissolved iron. The other went into the birch leaf dye bath together with the mordanted piece and a slug of dissolved iron.



And here is how they turned out. On the left, the alum premordanted fabric has taken up the birch leaf dye with iron as a khakhi background colour and the leaf hammer prints have taken up both the modified dye and extra iron and gone brown. In the middle, the unmordanted cloth that went into the dye bath has picked up a tinge of background colour while the prints have gone brown. Finally on the unmordanted cloth that was heated in iron and water only, you can see the leaf juices in the hammer prints have taken up iron from the water to make grey silhouettes of variable darkness, presumably according to their affinity for iron.

Japanese Acer leaves make a pink fresh print with no apparent colour along their veins, yet the juice in the veins must picking up more iron, as the veins come up much darker than the rest of the leaf.

In future, I think I shall experiment more using unmordanted cloth with just an iron and water bath. The leaf prints go black within ten minutes of heating and you can rinse the cloth straightaway, getting rid of most of the residual iron on the fabric without washing out the leaf shape. Quick and easy method for making rather a striking contrast print. Might be nice to put a single leaf silhouette on a shirt. Or cover up a stain on the front.

Friday, 11 May 2018

A Trial of Birch Leaf Dye

My companion, Elinor Gotland, watched me empty out a pocket stuffed with birch leaves.
"I suppose you'll be boiling that lot up and stinking out the kitchen again."
"Simmering, Elinor, not boiling. I've no idea if birch leaf dye will smell, the books never say anything about that. And yes, the dog and I had a lovely woodland walk, thanks for asking."
"Mmmm, no sooner have the trees sprouted a few leaves than you go pulling them all off."
"I only stripped a twig from each silver birch I passed. Just going to check how much I've got."
"Oh, you're not weighing those leaves in the kitchen scales, are you? They might be covered in bird poo or anything."
"Oh hush, I'll give the dish a wash. Smile, why don't you, this is the beginning of an exciting new dye experiment."
"Not if you're a birch tree, it's not."


My fresh birch leaves weighed just over 100g. Ignoring Elinor's grouchy temper, I added water to the pot, simmered them for an hour and left them to cool. Jenny Dean's book Wild Colour said birch leaves would dye an equal weight of fibre which had been mordanted in advance, so I planned to add 100g of premordanted wool.
Three 25g skeins of Shetland wool yarn were already prepared, on the left, one mordanted with 10% alum, in the middle, one mordanted with 2% iron and on the right, one mordanted with 2% copper solution.  To take another look at the difference between using iron and copper either as mordants or as modifiers after dyeing alum mordanted yarn, I wanted a fourth 25g skein, so I put another Shetland one in with some other wool yarn I happened to be mordanting in alum.
A sample of the birch leaf dye bath looked pale yellow and tested mildly acidic with pH paper. Adding a little soda ash to a second sample deepened the colour, but I thought this time, I would not meddle with the pH of the whole bath, just leave it as it was and concentrate on the effects of metal mordants and modifiers.
All four skeins went into the dye pot with the leaves still in it, together with a small piece of unmordanted cotton and a piece of linen mordanted with aluminium acetate. They were simmered for nearly an hour and left to soak overnight.
Taking them out next day, at first I thought I had got my labelling mixed up. According to my routine, a skein with iron mordant gets a yellow plastic clip, a copper one has a white clip and the two alum mordanted skeins should have pink clips. After a pause for staring at the wool and thinking about recent results with daffodil, dandelion and ivy leaf dye baths, I decided the brownest colour was typical of iron premordant and had been correctly tagged and the warmer toned skein was likely to be copper as shown by its white tag. Which left the two pink clipped skeins, the first two on the left of this photo, both alum, but not identical, one being a much deeper and more vibrant yellow green than the other. 
Elinor had hidden herself in a shady spot, where I hoped a long, cold drink might be improving her mood.
"You won't dry that wool by breathing all over it, Beaut. And it won't do the colour any good to hang it in direct sun, it'll fade.That sheep is paranoid too much sunshine will bleach her fleece and still inclined to grouch at me. "What's a May Bank Holiday for, if not getting sunburned? Or awfully dehydrated?" Elinor clinked her ice cubes and bit into her cucumber slice. 
"Half a minute now, I'm trying to think."
"Ah, is that why you've gone all red in the face?"
"This second alum mordanted skein - I may have made a mistake with my calculations."
"Again, Beaut? It's no surprise you were in the Remedial Maths class at school."
"I think I mordanted it with 20% alum instead of 10% by weight. I put it in to mordant with some skeins of aran yarn and I reckon I must have done the whole lot wrong."


Before completing the planned trial, I took the paler skein of alum mordanted yarn and divided it into parts. One part was saved just as it was, representing my usual 10% alum mordant. In this photo, it is the little drab shein on top of the larger one, which I think had a 20% alum mordant.

Birch Leaf Dye on Alum, Iron and Copper Mordanted or Modified Wool and Aluminium Acetate Mordanted Linen

A short length of the 10% alum mordanted yarn was soaked in alkali solution, just to get an idea of what alkalinising a whole dye bath might do. It turned a brighter yellow, though not as saturated a shade as the 20% alum mordanted yarn (left). Another part of the 10% alum yarn was simmered for five minutes with a splash of iron water to modify it, turning a grey green, whereas the iron premordanted skein was much browner (centre). The final part of the 10% alum mordanted yarn was simmered with a splash of copper solution, turning it a green gold, less gingery than the copper premordanted skein (right).

Birch leaf dye has proved well worth a trial and it does look as though adding soda ash to alkalinise the bath would bring up the colour even more. As before, the effect of modifying alum mordanted yarn with iron and copper pleases me better than the effect of actually mordanting the yarn with iron or copper beforehand. After my probable miscalculation, it seems to me I should consider using a higher percentage of alum to mordant wool in future. The older dye books often specify using more mordant than modern authors recommend, could be the old girls knew more than they have been credited with. Hey ho, I already have some skeins which I think were accidentally mordanted at 20% by weight, they were Drops Alaska on sale at cut price from Wool Warehouse, so it won't cost a bomb to buy some more and do a few more experiments. And there are masses of birch leaves and far more to come.

Friday, 4 May 2018

A Trial of Ivy Leaf Dye

Allowing the front garden to grow wild looked delightful earlier this Spring, a succession of bulbs bloomed in the lawn to the admiration of at least some of my neighbours. Now things are getting that bit too shaggy, crossing the line between naturalised and neglected. Ivy has grown over the wall and nobody appreciates walking into a wet slap of leaves. After I cut back the worst, it occurred to me that I had read somewhere you can make dye from ivy leaves. Taking a tea break, I found a page all about ivy in Jenny Dean's book, Wild Colours. Jenny writes that ivy leaves and berries will dye an equal weight of material and are best suited to animal fibres.
There were few berries left on the pruned branches, though easily enough leaves to fill my dye pot. They weighed about 300g. Adding water, I put the pot on the stove to simmer and went looking for some test fibres to soak ready for dyeing. Lifting the lid an hour or so later, the leaves had softened and the rising steam had a tang of rhubarb about it, so something was being extracted, although the water in the pot had no apparent colour at all.
Testing a sample with pH indicator paper showed the ivy had at least made the clear fluid acidic. Adding dissolved soda ash to another sample worked like magic, a lucent yellow green instantly appeared in the jar. A teaspoonful of soda ash brought the pH of the dye pot up to neutral, green colour appeared and convinced me there was dye in there, so I added my trial fibres in with the ivy leaves and turned the heat back on. Giving the pot a stir ten minutes later, the green glow in the water had all disappeared again and the fibres hadn't taken on any colour at all. That rhubarb smell in the steam must mean acid release, because indicator paper showed the pH had already dropped back down to acid. I added another teaspoon of soda ash, completed the hour of simmering and left the pot overnight.


Next morning, the fibres had gone green and the dye bath fluid looked brown, though when I retested it, once again, its pH had become acidic. I suspect that my two teaspoonsfuls of soda ash provided far too little alkali to counterbalance the acidity from stewed ivy leaves and that my attempt to alkanise the bath had had little effect on the overall ivy dye process.
Here is how the fibres looked straight from the dye bath - from the left, two skeins of alum mordanted wool yarn, next, one iron premordanted skein and one copper premordanted skein and the piece of linen mordanted with alum acetate. The unmordanted cotton fabric had not taken up significant colour. I divided one of the alum mordanted skeins into two smaller skeins and one short length. The short length was soaked for 20 minutes in an alkali solution. One small skein was briefly reheated with an iron solution to modify its colour and the other was modified with a little copper solution. 

Here is the final result of ivy leaf dye using twice as much weight of leaves as wool. On the left, alum premordanted skein with a bit on top that was modified with alkali after dyeing - far from improving the colour, it diminished it. Bottom row, a brownish version on the iron premordanted wool and a good green from the copper premordant, then just to mix things up, the two small skeins on top show a bright green from alum premordant and copper modifier and a dull green from alum mordant and iron modifier.


Ivy leaves are plentiful, more are coming over the wall already, it's good to know I can make green dye all year round. In future, I shall not be adding any soda ash, just trusting that the colour will develop once the wool is in with the softened leaves. I would certainly consider copper a useful premordant. As a modifier, copper took effect much more quickly than usual - I am only just realising that to modify dyes well with copper, you really need to add it in an acidic bath.

Here's a green wool heart for the Green Man as he dies and lives in the force of Spring.

Friday, 27 April 2018

Metal Mordants and Modifiers on Plant Dyed Wool


"Will you look what you're doing with that wool, you're splashing water all over me."
My companion, grabbed a tea towel to wipe the screen of her beloved mobile phone while I carried on slopping wet yarn from one bowl to another.
"I think that was mordant solution, Elinor."
"Have a care, Beaut, my insurance won't cover damage by toxic waste."
"For goodness sake, there isn't enough alum left in here to pickle a gherkin. This is the third time I've reused the solution and I'm just about to pour it away." I squeezed out a skein from the rinse water and twanged the loop to straighten the yarn. Elinor dodged away from another shower of droplets.
"Well, you must have started with pounds of alum to mordant all that wool. Why aren't you using your home made jars of iron and copper solution and being more ecofriendly?"
"Hark at you, Mrs Organic, glued to the internet all day."
Elinor sat back down at a safer distance and reopened her device.
"I am doing the crossword in The Guardian Digital Edition. Which means I no longer buy a daily newspaper and I'm saving trees."

Mordanting wool with iron and copper involves heating up dilute solutions in pots, consuming more energy if less time than a cold soak in alum mordant for 24 hours. A few years ago, I tried premordanting yarn by pouring a glug from my jar of rusty nails into one pot of water and a glug from my jar of copper piping into another. Having no idea how much iron and copper had dissolved into my home made water and vinegar mixture, I guessed I'd overdone it when the iron mordanted yarn turned strongly orange and the copper mordanted yarn turned quite green. Though I wasn't wildly excited with the dull brown results of dyeing the iron and copper premordanted wool with comfrey or with meadowsweet, both plants only give muted colours whatever the mordant.


Referring back to Wild Colours by Jenny Dean, I read that as mordanting solutions, iron and copper should both be used at 2% the weight of the wool. In order to be sure how much metal I was adding, I followed the instructions and dissolved 15g of ferrous sulphate and 15g of copper sulphate with 150ml hot water in two jam jars. 
Knowing 10ml of either solution would contain 1g of metal, I added 20ml to two pots of water, each containing 100g shetland wool yarn. I heated the one with iron for 15 minutes then rinsed the wool thoroughly in four changes of water. Once dried, the yarn was pale orange and the water still looked a rusty colour.
Jenny says to add white vinegar to enable wool to absorb copper, then to heat it for an hour before rinsing. Once rinsed and dried, the wool had turned pale green and the water in the pot had cleared leaving no trace of blue.
All this took place a few weeks ago, when the weather had just started to warm up and the slugs had awoken from their winter torpor and begun to feast upon my daffodils. Deadheading what was left, I picked 250g fresh, if rather wilted and chewed daffodil flowers which I soaked overnight then simmered for half an hour in water with a teaspoon of soda ash to get the pH up to 8. I added five 25g skeins of shetland yarn, one mordanted with copper and one with iron, two mordanted with alum and one with no premordant at all. Here is how they looked straight out of the dye pot, in that order starting with copper on the left.


My biggest surprise was how well the unmordanted skein (right) had dyed - previously, wool without a mordant has picked up only the palest colour from daffodils. The copper and iron mordanted wool both looked dingy shades of brown. Four of these skeins hung out to dry, cured for a few days, then had a good rinse. 

Dividing the remaining alum mordanted skein into two, I modified the colour of one part by heating it in the leftover copper bath and the other part in the iron bath. I'd forgotten that the added vinegar had made the copper bath acidic, which brought the yarn's pH down from alkali and immediately robbed it of much colour.



Once dried, the alum mordanted daffodil dye (left) was not half as yellow as I've had in other years. When used as premordants the iron and copper made the yellow dye into shades of brown, while when used as modifiers on the smaller skeins of alum premordanted yarn, I had a dim orangey beige from iron and a grey green from copper (though more green than the photo shows). Not what I've had when I've modified daffodil dye before, confusing and rather discouraging results. All things considered, this attempt to explore the difference between premordanting and modifying plant dyed yarn with iron and copper turned out poorly, though there is undoubtedly a big difference in the effect both metals have when used in the two different ways. 

Last week, the weather turned gloriously warm and the roadsides sprung wild with bright dandelion flowers. It only took me 20 minutes to gather over 500g, the right weight for the five to one, plant to wool ratio which I wanted in order to repeat the same experiment with another 100g shetland yarn. The sudden summer heat may be the reason that this year, I had a far brighter yellow from dandelion flowers on alum mordanted yarn (top centre). Previously, in cooler Springs, it has been much more of a dim and greenish shade. The iron mordant came out brown (left), but modifying some alum mordanted yarn with iron gave an entirely different olive green. The copper mordanted yarn turned a more golden version of yellow while the copper modified alum mordanted yarn came out lime green. Much more in line with previous modified dandelion dye experiments.



My companion and I sat on the patio drinking Pimms, her doing the crossword and me admiring my dandelion yarn and enjoying the foretaste of summer heat.
"This is the life, hey, Elinor?"
"Global warming is hardly something to celebrate, Beaut." She looked up, waved her hoof at an unseasonable wasp zooming in on the fruit slices in the jug, then frowned at me. "After all the sunshine, that grass needs cutting." As the wasp buzzed around her head, Elinor stood up and stepped backwards into a terracotta pot. "Not to mention how late you've left it to get these pots planted up." Jinking around the patio with an enraged wasp following her, she finally put down her phone and looked about for a more suitable weapon.
I sipped my Pimms.
"Bet you wish you'd bought a real newspaper now."

Friday, 20 April 2018

Oak Gall and Oak Bark Dye on Wool at Acid and Alkali pH

"Ye Gods and little fishes, is there no end to your boring brown bark dyes?" 
I cowered at the fearsome glare of my companion, Elinor Gotland. 
"Well, I did think the yarn might come out more pink."
"Pink? Whoever told you oak would dye wool pink?"
I shifted uneasily in my chair.
"Actually, I said that myself. I know I got pinky brown colours from oak galls and from oak twigs and again from acorns when I dyed with them before. Seems I've been a mine of misinformation about oak as a dye and a tannin mordant."
Elinor put down her oak twig.
"Wash down the humble pie with some other brown tannins, Beaut. You've left your tea bag brewing long enough to strip paint."

This past couple of months, I've been much interested by the way a week of fermentation in cold water makes bark dyes acidic. Simmering yarn and fabric in a fermented bark dye bath has given pale colours, increasing the pH with soda ash has not only deepened the colour, but in the case of silver birch, transformed it from beige to pink. All done with no need to mordant wool or cotton in advance.


Hoping to explore a little more of this alchemy, I went looking for fallen oak branches. Although there were heaps of fresh twigs under the trees in autumn, in March I found only crumbly old wood and one small branch to peel. On the leafless trees, dried up oak galls were easy to spot and no trouble to pull off.
Coming home with a 200g haul, mostly oak galls and a handful of peeled oak bark, I broke the galls up with a hammer and left the lot to soak in a bucket of water for a week or so. After simmering it in a pot for an hour, I sieved the bits out of the dye bath through a piece of old net curtain. 
Three 50g skeins of unmordanted wool yarn were simmered for an hour. Having tested the dye bath to check it was the expected acidic pH 5, I wasn't surprised that the wool went beige. Taking out one skein, I added dissolved soda ash to bring the dye bath up to neutral pH 7 and simmered it again before taking out another skein. Which had gone brown.
Deciding to bash on anyway, I increased the dye bath to alkaline pH 9 and gave the last skein a final simmer. It came out a dimmer, duller brown.  Here are samples of the dye bath at each pH. The more alkaline, the blacker the bath got, but never a hint of pink in the wool it dyed.


Wool Dyed with Oak Bark and Oak Galls at pH 5, pH 7 and pH 9

The yarn was left to cure for a week then each skein was rinsed separately and allowed to dry again before I brought all three outdoors to examine them in natural light, drink tea and have my work critiqued by my dear companion. 


"Did you save those bashed up oak galls, Beaut? There'll still be plenty of tannin in them."
"Yes, they're in that bucket of water. Don't think I'll use them to dye anything else, but I might try mordanting some cotton."
"Don't go getting that wrong, like before. You'll need to mordant the cotton with alum as well, then put it back in the tannin bath."
"I know, I know. Hardly seems worth the bother, when a single bath in a 5% solution of aluminium acetate will mordant cotton and linen perfectly well."
Elinor treated me to another of her looks.
"That's not a very enterprising attitude. I thought you were going to grow your own ecofriendly soy beans this year and try mordanting with them."
"Soy milk isn't a mordant, it's a protein binding agent. And no, I'm not planting soy in my garden."
"Just going let someone else chop down a rainforest and replant it with a genetically modified soy monoculture?"
"Just going to ignore the whole soy option, Elinor." 
"I had a friend who swore by soy milk for ecoprinting cotton."
"Yeah, and I've got a friend who's going swimming in a bucket of oak galls in a minute." 
Exit Elinor, pursued by a bear. A brown one.

Friday, 13 April 2018

Alder Bark Dyes at Acid and Alkali pH

"Not more bark dyeing, is it, Beaut?" My companion, Elinor Gotland, opened the back door to let out the heat. "It's like a sauna in this kitchen."
"Oh, good, I thought it was just me."
Elinor wiped the steam off her specs and watched as I unbuttoned my cardi and flapped the bottom of my T shirt.
"I thought you were past all that."
"So did I, but the hot flushes are back worse than ever."
"Ah, the Menopause Fairies bring many gifts."
"Menopause Fairies? I never heard any stories about them."
"To be honest, Beaut, not many people have. They just don't get the same media attention as the types that cluster round the crib, getting in all the Christening photos. Fifty years on, nobody brings a camera to anyone's Festival of Changes, but Sweaty Betty the Hot Flush Fairy is usually the first to turn up and the last to leave."
While Elinor was talking, I had turned down the heat under the pots.
"Drat and double drat. I didn't mean to let them reach a full boil."
"That'll be Slack Alice visiting you with her fairy gift of Inattention. What have you got in there anyway?"
"This pot is another silver birch dye. While I've plenty of fresh bark available, I thought I'd have another go at dyeing cotton and see if changing the pH makes as much of a difference as when I dyed wool."
"And the other one?"
"I'm doing another pH experiment, using alder. Had to peel branches for bark, because rainstorms have washed all the fallen cones out of that ditch where alder trees grow."
"You know full well what'll happen when you increase the pH, you've done it before."
"Have I?"
"Yes, last year, you knitted that bag with alder dyed yarn. Then you put it through the washing machine with ordinary washing powder and it changed colour. You remember, washing powders are always alkaline, same effect as soda ash."
"Oh. Maybe you're right." 
"Goofy Gladys is the Memory Fairy."
"I don't think I like these Menopause Fairies. Are there many more of them?"
"Well, there's Gladys' best friend Grace, who makes you bump into things. And watch out for Gloria, the Gravity Fairy, who grabs any dangling parts ..."
"Enough. I shall combat Gloria with an underwired bra."
"You'll need a full metal jacket for those, Beaut."
I heaved a sigh and turned back to my dye pots.


Two hundred grams of alder bark had been soaked in a bucket of water for a week. Testing with a strip of indicator paper showed fermentation had made the water mildly acidic at pH5. After simmering for an hour, I left the bark in the pot and added three 50g skeins of wool yarn, simmered them for an hour and left them to cool before taking out one skein.
This time, I thought I would alkalinise the dye bath using wood ash, so I took a tablespoonful from the grate and put it in a jam jar with some water. Once the ash had settled, the fluid tested strongly alkaline. Unfortunately, you would need far more than one jar full to alkalinise 10 litres of dyebath, so I had to add some dissolved soda ash too.
With the vat brought up to neutral pH 7 and simmered again, the wool wasn't changing colour perceptibly, so I added more soda ash to make it mildly alkaline at pH 8.
After the pot had cooled, I took out the second skein, increased the pH to 10 and simmered one more time. Here are samples of the dye baths at each pH, though rain wrecked the indicator strips before I could take the photo.


Alder bark dyed wool yarn at pH5, pH8 and pH10



The dye bath still looked dark, so I added a slug of iron water and simmered another 100g skein of wool, getting a saddened version of the alder dye colour which is shown on the far right. All the skeins were left to dry for a week after dyeing, then rinsed separately in several changes of water.


Knitted into stripes with some undyed yarn, a small swatch did not run or change colour when washed with pH neutral washing liquid in the washing machine on a 30 degree wool cycle. I've found both silver birch and alder bark dyes seem washfast and stable as long as you don't mess with the pH after dyeing. I've taken on trust the idea that the tannin in bark means that wool doesn't need to be mordanted before using bark dyes. Which is confusing, because tannins are supposed to be part of the mordanting process for plant fibres like cotton, but are not supposed to be effective mordants for animal fibres.


The All About Bag I dyed with alder bark and cones has got rather battered over the past year. It wouldn't ever have been quite the same colour as the new skeins, but looking at it now, I'd say it has proved lightfast and I am confident that whether that is due to tannins or not, no premordant is needed before dyeing wool with bark.
My companion found me comparing the old with the new.
"Ooo, super duper, once again you have discovered that alder dye is brown and even more brown when it is alkaline."
"I think the colourway is rather lovely, Elinor. Even the beige from the acidic dye bath."
"You'll be wearing elasticated slacks and a camel cardi next."
"So what if I do? I'm happy."
"Ah, I see you've met Frankly."
"Frankly? Bit of an odd name."
"Well, Beaut, she's an odd fairy. Whatever you called her, Frankly wouldn't give a damn, a toss or even a flying fuck at a rolling doughnut. She'd live in a boiler suit, if it weren't for the trauma of going for a pee."
"I like the sound of her much more than Sweaty Betty and Goofy Gladys."
"Fair play, she's, how can I put this ... unconventional. Alternative. You'll remember from the fairytale christening stories, there's always one fairy who appears at the last moment with a gift that subverts all the others. As far as the Menopause Crew are concerned, that's Frankly."