Woad - growing, harvesting and dyeing

I'm completely obsessed about woad.  The plant is a relative of the cabbage and it creates a gorgeous blue dye.  There's a long history of it being used in Medieval times and before.  The great thing about it, is it grows well where I live with very little effort.

The blue dye in woad is the same as in Indigo.  We have a lovely long thread about this dye and the plants that create it.  But I thought, why not have a thread just for woad?  

Indigo doesn't grow well where I live.  It needs cosseting, extra irrigation, soil fertility and all sorts of added effort that I'm not interested in giving it.  Even though Indigo is more efficient than woad - it produces so much more dye per weight of plant than woad - it is less efficient for me to grow indigo.  I don't think that makes sense.  But basically, for a tiny amount of effort, I can grow massive amounts of woad and get nearly unlimited blue dye while helping to break up compacted soil.  For a lot of effort, I can grow a tiny amount of the more efficient indigo plants and get an itty bitty amount of blue dye.  

I'm going to focus my energy on growing woad.  Although I admit, I'm still getting to know this plant and what it can do.  That's why I started a thread about it, so we can learn together.


Growing Woad



My cute little baby woad plants from last spring.  I started them indoors last March and planted them out when the frost started to lessen in early April.  The ones I planted out after the last frost did better and gave me an extra harvest, so this year I'll plant them out later.

I grew my woad in an area with poor, excessively well-drained soil, and zero irrigation.  They had no water or rain from May 1st through to October and did well.  They thrived.  I got three harvests from them, and could probably have gotten four more.  But I wanted to leave the plants to gather energy and make seeds.


Harvesting the dye was interesting.  The first attempted, I tried the extraction method which gives a blue powder that we can store and use later.  One kilo of leaves gave me 1 gram of blue powder which (according to what I've read) dyes about 10 grams of fibre.



For the next harvests, I tried making woad balls.  The leaves are mashed up and then shaped into a ball.  The theory is that the balls ferment inside as they dry and convert the dye into a useable form.  



What I liked best with this method is that it was purely mechanical.  No heat, no excess water, no chemicals.  This is a traditional European method and I'm looking forward to experimenting with woad balls this year.


Some more links about woad.

http://www.jennydean.co.uk/wonderful-woad/

https://www.sciencedirect.com/science/article/pii/S2352409X14000273

A video about harvesting woad on a hillside, extracting the dye and fermenting it with urine to create a blue-ish coloured t-shirt.  

Woad is on my long list of plants to try growing this year. I'm not sure that I'll be buying seeds for it, as I have so many other things I want to try, but I am definitely interested in woad. One of the things I wonder, especially as you say it grows with little care, is whether or not it's likely to "go rogue" and try to colonize neighbour's yards?

Vera Stewart wrote: One of the things I wonder, especially as you say it grows with little care, is whether or not it's likely to "go rogue" and try to colonize neighbour's yards?

That's a very good point.  In some places, woad is considered an invasive species.  In those places, it might be better to harvest wild woad instead of growing it in the garden.

Before I started growing woad, I looked into this.  It wasn't on our invasive list or on our watch list of potential invasives.  I'm also not so sure how well it will reproduce because we don't often get a cold enough winter.  I have trouble getting kale to flower some years.

But to be safe, I'm growing it in parts of the farm that are apart from the neighbours.  It's biannual so I plan to do a strong harvest at the end of summer of all but a few plants for seed.  The ones that do go to seed, I can place the stocks in a paper bag at the end of the maturing time.  This will prevent the seeds spreading or getting eaten by birds.  

dyeing with woad balls

To sum up: Woad balls can be used in the same way as fresh woad leaves, except that the leaves should remain in the vat throughout. Whisking may not produce any blue froth but ignore this & continue as usual. The vat itself will not look like the more usual woad or indigo vats, but this does not seem to be of any importance. The vat can be kept going over several days & the colours from this type of woad vat will be more green in tone.

I wonder if this is the author of the dye book I like that has loads of different ways of dyeing with woad in it?

sewing woad seeds

It is warm enough to sow woad seeds in the UK when daffodils are in flower.

some more information on woad cultivation

Last year, I started my woad indoors and planted some out in March and more out after the frost stopped in April.  The April ones did better and I got three large harvests off them (about 1 kilo per plant total) and could have had two more harvests.  However, the earlier ones didn't do as well.  This might be because I didn't harvest them?  Or because they were in different soil?  Or less sun? Or some other reasons I don't know what.  

Last year, it was about half a dozen plants.  Just enough to see if they will grow (check), produce a harvest (check), and produce blue (check).

This year, a few more plants.  I want to experiment with different methods of working with this plant and I need a a bit more than a kilo at a time to make it work.   I want to dye yarn in 100g batches, which (according to theory) takes 10 kilos of fresh leaves.  At least that's the theory... some reading suggests it's a lot less.  

After this year, I'll discover if I love this plant or just like it.  If I love it, I'll plant more and sell woad balls.  If I don't, then I'll just keep enough for personal use.  

a traditional method for extracting blue dye from woad

Historically speaking, woad indigo was always extracted through a long and laborious fermentation process. ...

...woad leaves are first harvested, and then ground up on a giant woad mill. ...

When the woad leaves were crushed, they were piled in small heaps to drain. Once the woad was dry enough to be cohesive the piles were pulled apart and formed into woad balls. The woad balls were anywhere from two to six inches in diameter. These woad balls were then dried in specially constructed drying racks, exposed to air movement but shaded, to prepare for storage. Dried woad balls could be stored indefinitely before couching.

There are a lot of good write-ups on this site.  I think this person has a lot of first-hand experience working with woad.  Well worth a gander.

Ah, it is listed as growing here in Montana, mostly unwanted! I learned that some call it

"Dyer's Woad" - Isatis tinctoria

Kingdom - Plants - Plantae
Division - Flowering Plants - Anthophyta
Class - Dicots - Dicotyledoneae
Order - Mustards/Capers - Capparales
Family - Mustards - Brassicaceae
Species - Dyer's Woad - Isatis tinctoria

The names above and pictures below are from here:  http://fieldguide.mt.gov/speciesDetail.aspx?elcode=PDBRA1K010.



The flower sure does look like a mustard flower!


I think I've seen this growing here at base camp! I'll look for it this growing season. It's a plant I keep looking at, thinking I should know what it is, but haven't been able to place it in my memory.

Here are some links to posts in this thread Indigo blue - growing, harvesting, processing and marketing indigo dye plants with some extensive information about woad from Daniel Schneider...
https://permies.com/t/37159/fiber-arts/Indigo-blue-growing-harvesting-processing#543251
https://permies.com/t/40/37159/fiber-arts/Indigo-blue-growing-harvesting-processing#543896
https://permies.com/t/40/37159/fiber-arts/Indigo-blue-growing-harvesting-processing#544279
https://permies.com/t/40/37159/fiber-arts/Indigo-blue-growing-harvesting-processing#544313
https://permies.com/t/40/37159/fiber-arts/Indigo-blue-growing-harvesting-processing#547741
https://permies.com/t/40/37159/fiber-arts/Indigo-blue-growing-harvesting-processing#574513
https://permies.com/t/40/37159/fiber-arts/Indigo-blue-growing-harvesting-processing#578116
https://permies.com/t/40/37159/fiber-arts/Indigo-blue-growing-harvesting-processing#590115

and links to my own small experiment with woad in growing, harvesting and using natural dye plants and other natural dye materials

It is a wonderful plant.  I grew some very nice ones and did only a small dye experiment.  I let some go to seed and have never had a volunteer...in fact find them difficult to germinate other than in a flat that I can monitor and keep moist.  Once they are in the ground they take off and survive winter cold here (although maybe not this winter as we had some single digit temps a few times).  I'm having trouble sourcing seed this year and mine got too old to germinate well.  It seems both Richter's and Strictly Medicinals have stopped selling it?

I saw it in my print Richter's...

Yes, here it is online. Woad availible from Richters.com

They will not ship to Idaho, Montana, California or Alberta

Anyone know if geese eat woad?  I'm trying to decide what sort of protection to give my woad in their new bed.  The roots. Are supposed to be good for breaking up hard pack soil, so I want to grow them where the so called lawn is.

At my place, Dyer's Woad is a biennial, so it germinates in mid-to late summer, overwinters as small plants, and flowers the next spring.

Sheep and goats love to eat Dyer's Woad. I don't know about geese.

some technical stuff about how the chemistry works


Another link about growing and harvesting woad

this link talks about some in-depth research into growing and using woad, and the possibilities and practicalities of scaling it up to an industrial crop.


I found the research into the specific bacteria used to ferment woad interesting.

Professor Philip John from Reading University who had been doing some interesting microbiological research on the mediaeval fermentation vat used in a re-enactment at Chiltern Open-Air Museum by John Edmonds.  They described a new species of Clostridium bacterium (C. isatidis) which was responsible for chemically reducing indigo in fermentation dyeing vats, based on a mediaeval recipe.

It's also interesting that different strains of woad produce different amounts of indigo precursor.  

I have ordered some woad seeds!

Do you have any experience growing it in large pots? I'm wondering if it would be "safer" in terms of trying to avoid introducing an unwanted invasive to my neighbourhood by accident if I grew a couple of plants in large pots...but perhaps the roots are too big/strong?

Vera Stewart wrote:I have ordered some woad seeds!

Do you have any experience growing it in large pots? I'm wondering if it would be "safer" in terms of trying to avoid introducing an unwanted invasive to my neighbourhood by accident if I grew a couple of plants in large pots...but perhaps the roots are too big/strong?

Congrats on starting your woad journey.

I start mine in pots indoors but haven't tried growing them all the way to harvest in pots.  It might be worth trying it to see how it goes.

One of the things that attracts me to woad is that it has a deep root that is good at breaking up hard soil.  

From my reading, the invasive nature of woad comes from the seeds in year two.  This is where I'm going to focus my containment efforts.  Only let a small number go to seed and kill off the rest of the plants.  

Thanks. I have quite sandy soil, I think there is about three maybe four feet of it until the rocks of the mountain start getting seriously in the way. I will reserve decision on whether or not to plant the woad out in large pots or into the ground until I see how other planting goes this spring.  

Aplogies if you've already said somewhere in this thread - how long did it take for your woad sprouts to start coming up? I planted my seeds in trays March 25th and I don't see anything coming up yet.

Vera Stewart wrote:Aplogies if you've already said somewhere in this thread - how long did it take for your woad sprouts to start coming up? I planted my seeds in trays March 25th and I don't see anything coming up yet.

Sometimes the woad seed I get doesn't sprout at all.  I don't know why.  Maybe too warm?  Maybe old seed?  I wonder what the half-life of woad seed is.

When it does sprout, they are usually up in less than two weeks.  

Sorry R, I somehow missed your reply.

I finally had five seedlings come up, for now I have three in a large pot and two I planted directly into the soil. This is exciting!

What they say about not needing many woad plants for seed is correct.  Sorry I doubted you.

I thought, hmmm... one plant doesn't give that much genetic diversity.  12 plants would be better.

I now have a lot of woad seed.  Even though I hope to grow this on a large scale, I think I only need 200 seeds a year.  Doing the math, it looks like I have enough for roughly 40 years.  Only the shelf life of woad isn't all that long.  

A solution presented itself in the book WildColour by Jenny Dean.  She says we can use woad seed for dye.  

It looks like woad seed produces a pink-mauve colour without a mordant, and variations of mauve-blue-green with different mordants.  

In the heart of the problem is the seed of the solution.  Or perhaps in this case, the seed of the problem is the heart of the solution?

One interesting aspect of this plant is that it is perhaps one of the most effective anti-virals available, according to Stephen Buhner, well-known herbalist in his book "Herbal Anti-VIrals".

Apparently it grows wild in E. Oregon, so I hope to find a patch and make a tincture out of it.

I have done some dyeing and in the future I would also like to dye with it.

JohN S
PDX OR

Woad seeds in a boil water bath, on alum mordanted wool.

I suspect there was a touch of iron in the pot where I boiled the woad, so it turned out less pink than I expected.  But still nice.  

My first attempt at woad leaf chemical dye vat failed.  I couldn't get the froth to turn blue, even after 20 minutes of pouring it back and forth between two pots.  

Possible errors
- too base?
- too hot (I kept it in the sun so it wouldn't cool down, but even after a few hours, it was too hot to put my gloved hand in)?
- something else?

I'm going to try again in a few days.  I've got over half the plants left but they are dying back quickly in this heat.  

I love this process of learning how to do something and figuring it out.

Thanks for even sharing the parts that didn't work, r ranson.

It always surprises me in a good way when I can figure out how to make it work.
John S
PDX OR

Thanks.

I wish I knew why it went wrong.  

Here's what I did.

1. Harvest leaves and tear them into 2-inch chunks.
2. pour boiling water over the leaves.
3. wait an hour or so then strain the leaves, being sure to squeeze out as much juice as I could.
4. add a small amount of lye.
5. airate.  After 10 minutes, add quite a bit more lye and airate for another 10 min.  No blue froth, keep going anyway.
6. reheat
7. add the reducing agent.
8. attempt to dye yarn.

I think somewhere from 2 on was my mistake.  

For the next try, I'm going to do things less by the book.  In full sun, the garden hose water gets scalding hot, so I will probably use that for stage 2, then skip stage 6.  If I keep the vat in the sun then it should be warm enough.  possibly.  

It's been awhile and I only tried one dye batch of woad although I've grown it off and on for several years.
I didn't try a vat, just step one and two of your list above.

Here's the link https://permies.com/t/15888/fiber-arts/growing-harvesting-natural-dye-plants#274420

I don't even remember what the fabric was?? But I also have a tuft of wool from that batch that has held it's color well.
https://permies.com/t/15888/a/16091/natural-dye.jpg

Neither are the deep deep blues obtainable with a vat though.

I have my woad seed back ordered at Richter's...still wanting to try....again...

Nice color from the seeds...makes me wish I had not composted so many of them when they got old.

I know you're not interested in using facebook but there are some interesting groups there discussing natural dyes.  One is devoted to indigo vats and covers woad also...another I am learning a lot from has to do with lichens and mushroom dyeing and the third is natural dye ferments.

All three have active real time problem solving discussions and are quite helpful.....natural dye nerds!!!

Maybe it's necessary to do the initial soak for longer than an hour?

Here is something from the dye group that might be helpful.  For the initial extraction the leaves are soaked for at least 24 hours in a covered tub in the sun and sometimes for days if starting with cold water....waiting for some of these possible indicators that it is ready to strain out the leaves...

Here are some indicators that you’re ready to take leaves out. Big emphasis on “Some” because you may not see all of these signs or they may differ slightly so don’t think of this as a checklist...

•The liquid in the vat has turned from clear to a yellowish bluegreen 'antifreeze' color
•There are bubbles forming on the surface
•There are blue pigment particles floating on the surface
•There's a coppery/oily looking sheen on the surface
•Most of the leaves have a slightly slimy film on them or the leaves have turned from bright green to yellow and look “spent”.
• you can also try the lime test with a small clear, lidded jar. Add liquid and a drop of lime and shake vigoriously for a few minutes, you should see blue pigment start to float.

Sounds a lot like the start of a fermentation vat.  Were they adding anything else to it before or after?

r ranson wrote:Sounds a lot like the start of a fermentation vat.  Were they adding anything else to it before or after?

My understanding was that this is the 'extraction' preliminary to either making a vat or dehydrating down to a pigment.

EDIT: this is a direct quote introducing her detailed instructions...  

This post details a form of aqueous alkali precipitation extraction starting from fresh Japanese Indigo aka Persicaria Tinctorium(any indigo bearing plant can be used, keeping in mind certain varieties of indigo contain more indican than others.) Fresh leaves are soaked in water, an alkali solution is added, aerated, settled, and strained to achieve a dry indigo powder pigment or paste. The pigment can then be stored and used in various Indigo reduction vat recipes.

Nothing added before, only a certain proportion of water to leaves left, covered, in the sun as a heat source.
After straining out the leaves she added hydrated lime and was aerating....very similar to your steps from #3 onward.

The more I read the more confused I am though...many, many methods and variations on them.

Today's attempt so far:

1. leave the long garden hose in sun, go inside and have breakfast.
2. use hot water from the hose to half fill a pot, put pot in greenhouse 120F (is that hot?)
3. make sure hose is still in the sun, go and gather woad.
4. tear up leaves and put them in hot water.  Add more hot hose water.  return the woad pot to the greenhouse.  Go inside and hide from the sun.  

Greenhouse now 130F.  Water hot enough I can barely keep my hand in it.

So far, less energy used.  Will the liquor get hot enough to extract the dye?  I don't know.  

Will the liquor get hot enough to extract the dye?

 

Now we are in suspense...
I think it just takes longer to extract the dye if it is cooler?

The greenhouse is now -60F (the thermometer goes in a circle).  The water was steaming hot and hurt to put my hand in, the colour was sherry coloured as expected.

I squeezed out the leaves and by then the water was cool enough to put my hand in but still quite warm.  

Added lye, a lot less this time.  The litmus paper says it's somewhere between 8 and 9 ph.  I'm not sure it's right because the water doesn't feel slippery.  

I poured the batch between two pots several times - about 40 - and got lots of lovely yellow froth.  But no blue froth.  So I took a break and tried again.  Same.  

It's too hot outside now for me to work, so I'm going to wait until the sun goes down and try again.  

I think this is my favourite resource so far

page 1 http://www.woad.org.uk/html/extraction_1.html
page 2 http://www.woad.org.uk/html/woad_pigment.html

I wonder if this will work

Another very effective way to aerate is by dipping a plant pot (of the type with holes in the bottom) in the saucepan (fig. 10). Lift it above the saucepan and let the liquid drip through the holes in the bottom of the plant pot, back into the saucepan. Using the plant pot is fun and less tiring on the arms than using a hand whisk.

Great thread! Thank you.
Woad sounds like a wonderful plant to introduce onto a little piece of land I just bought. Until now I've been mostly concentrating on edibles (fruits/nuts) but this opens things up a bit! I love the idea that I can also introduce plants like Woad and Indigo for dye experimentation. Wonderful...off to explore the fabulous links/info more in depth! Please keep posting about how your extraction and use experiments are going.
Kind Regards
Shari

Judith Browning wrote:I know you're not interested in using facebook but there are some interesting groups there discussing natural dyes.  One is devoted to indigo vats and covers woad also...another I am learning a lot from has to do with lichens and mushroom dyeing and the third is natural dye ferments.

All three have active real time problem solving discussions and are quite helpful.....natural dye nerds!!!

Any chance you could convince some of your woad friends to pop in here?

Failed again.  

We're on water conservation measures now, so I will probably make most of the rest of the plants into woad balls.  

But I still want to make one successful vat this year.  

Too much medicine in our diet for a urine vat.  

Maybe something else?