ALSO KNOWN AS: Isatis tinctoria, dyer's-weed, glastum, dyer's woad, satis in Aramaic, Färberwaid in German, Guède (French), asp of Jerusalem, glastum, wad (Anglo Saxon)
From a distance
Tall plants with a cloud of yellow.
You’ve seen this same scene in fields of mustard and canola - they are all closely related
The plant that protected ancient warriors, the Celts and the Britons
A foundational traditional Chinese medicine
Woad yeilds a strong indigo color. It has been used as a dye for thousands of years.
I first learned about woad in the late summer of 2024. I was quickly realizing that I would need to profoundly change my outlook on the way I was making money. My career was completely changing. I had to open up, to find more people in my life. I was desperately unemployed - with the only plan being that I wanted to write and stare at plants all day. I went to a free natural dyeing workshop one afternoon at Governor’s Island where I met a book maker and artist who grows plants there. Of course I felt jealous of her. Here she was teaching a cool workshop and I was just trying to find out what to do with afternoons so that I felt like I had a purpose in my life. On that crystal August day, I was falling into a life I couldn’t grab hold of. My future was going to kill me, I was going to disappear into it without a trace and it was terrifying.
‘Woad,’ the teacher said, ‘is indigo.’ So that’s what I thought it was, but it’s not. It turned out she meant the color, not the plant.
Bodies in Blue
But that doesn’t make this plant less authentic. Some plants are so valuable to certain cultures that they can’t be separated from the story of its people. I can tell all the stories I like about how valuable this plant is, but unless we feel it throughout our bodies, we can’t know.
Woad was first mentioned by colonizers of Northern Europe. Rome fought these tribes, like all colonial and empires, they slowly suppressed the language and stripped it of its cultural meanings, kneading them into the dominant culture or killing them. Though it took a long time for the Romans to declare themselves victorious. As it is with colonizers, they saw tribal peoples in crisis and called them all sorts of derogatory names. They called them what they looked like in battle because that’s all they, collectively, saw.
Imagine people emerging from the dark ancient woods of the British Isles, now only a memory from the stone walls and fences that make up the green islands. From these old trees lived peoples who made blue out of the most yellow flowers. These tribal individuals were patterned and spiraled in the blue. They wore matrixes of tartans with which to map their lineage and protect their bodies with its powerful chemistry.
The Romans called them ‘picti’ for the tattoos on their skin. In religious ceremonies of the druids, women were the ones who were painted blue.
The Iceni tribe, led by Boudica the female warrior and leader, likely wore woad as she fought against the incoming Roman empire. When in battle the woad was painted on the skin of various tribes throughout what is now Europe. Daubed on the skin it would last for about ten days, protecting the warriors and giving a timeframe for how long the battles could be. In other cases it was tattooed.
It is native to the steppe of the caucuses where it takes in lots of sun and wind, though some studies suggest it is native to Central Asia. Eastern Siberia and Western Asia. This is why one of its very close relatives, Isatis indigotica, is so prominent in traditional Chinese medicine and dye. In the Altai region of Russia it was a status symbol to be tattooed with woad. I can’t find medicinal uses for it there, but I would imagine they put this plant to use. Because it works.
Brassica plants really vary, they can be so many things. They are related to cabbage, kale, bok chop, mustard, canola, broccoli, and radishes, and Brussels sprouts, to name the popular ones.
The woad, similar to foxglove, begins as a basal rosette. Generally it’s a biennial, meaning that it grows as a rosette on the ground the first year, and the second year it grows tall and flowers. But depending on how strong its roots, it may flower for a few years in a row. It grows about 4’ tall, beside many weedy companions. Woad itself has 80 species that range throughout Europe and Asia.
Woad moved through the world as a dye and a medicine, which is how it came to the Americas. Until synthetic dyes were developed, woad was one of the three main sources of blue as a dye. Other than woad, there was the legume, indigo, which is more colorfast and longer lasting, and Japanese indigo, which is in the knotweed family. Strong in its own, woad has sodium ions that allow it to be used as a mordant for fixing other dyes.
They all share these yellow inflorescences: flowers growing at the top of the stem. Each of the tiny flowers has four petals and six stamens inside. The Cruciferae, or cross-plants, have four petals in a tiny cross. These flowers have both male and female parts.
It’s pollinated by bees, flies, and wasps, it’s not picky. The cabbage white and small white butterflies lay eggs and raise their young on the leaves. Eggs are stimulated in the butterflies when they interact with the glucobrassicin in the plant. This glucobrassicin has anticancer elements to it - a remedy for both bodies of the smallest and the largest animals.
Inside what looks like a yellow flowered plant, is blue - blue seeping from the stalks and leaves. They can be identified by a single creamy midrib. You can see blue pulses under the green running down their centers. These leaves are very nearly wavy along their side and they’re shaped a bit like wide oars that grow in an alternate formation up the stalk. But they do something different than many other leaves, they clasp the stem, like collared capes. When it is broken open it stains.
Seeds and dyed textiles were found from Bronze and Iron age sites throughout Europe. Now it acts like quite an aggressive species, primarily on the vast ranches beyond the Rockies in the Western United States, taking up where soil has been upended in bright yellow bandages, covering the earth like a mummy, like it needs to be contained. It grows in thick yellow mist over the bare fields. If it’s mown down it will come up again, blooming again in the same season - resurrected. The Egyptians wrapped their dead in blue, like a sunset, like the coming of night. But it’s useful if you know what to do with it. It doesn’t seem to mind rocky substrates. It grows in limestone. It tolerates heat and drought conditions. It thrives in rocky soil, a plant for arid climes and big sun.
The seeds are wrapped in water soluble fruit pods that protect it until the conditions are favorable enough to germinate. These pods hang from the top of the stem like black piano keys. They turn from green to deep blue/black. Chew these seeds and they’ll turn your spit blue. When the seeds emerge they have two halves that are not equal to one another.
In Medieval Europe it was used to cool the blood and treat the spleen. Medical practitioners believed it healed the curse of St. Anthony’s Fire - when people ate the ergot fungus. Now it’s known to be an antibiotic and antimicrobial and as a prophylactic, disease preventing. The leaf particularly helps the throat. Though generally it was used as a paste because it’s so astringent. That blue is the medicine in the plant, which might have been the reason why it was so important ceremonially for the Celts. Who might have seen the connection between its medicinal value and the blue it yields. Pliny the Elder wrote about it, a man of so many plants, mostly as a plant to be used for blue.
Woad, like its cross shaped flower cousins, became valuable in markets in Europe. Toulouse grew wealthy on woad.
It has been used in traditional practice from the celts to the Egyptians. In Ancient Egyptian culture, it was woad, not indigo, used to produce blue, from North Africa, throughout Europe, it was the plant that made blue. Far from its commercial success before indigo captured the world’s market, woad seeds were found in caves in France from the iron age.
Its astringent, so it can be used as a wound healer. This is marked in its name from the Greek, “Isadso” which literally means ‘wound healing’. It has antimicrobial and antitumor properties.
Despite its medicinal properties, woad is not often used as a food, but in Italy the infloresences have been used in omlettes and salads. Other than that there are not many references to its use as a food necessarily, it has been so long considered a medicine and dye.
Were the tribes of the British Isles looking for comfort in the chaos of battle? Blue is an absence. But it is the only color that reminds us how alive we are, how immense this world is. The sky and the ocean are blue: places where only ships go to ride the streams. Blue reminds us that everything changes. If we can remember that we can truly be here on earth. Blue is a color we can hold on to when the abyss looks us in the eye. It may calm our nerves if that abyss wears a blue dye.
Myth for woad
Text for myth, Music: Bach/Gounod “Ave Maria arranged for piano”, https://www.classicals.de/bach-gounod-ave-maria
Not to be confused with indigo. Indigo actually stays longer as a dye. It’s also a pea plant. You can tell right away by the flowers. They just look like stout beaks to me.
Or canola. This is a brassica plant. I swear, they all look the same with their little yellow flowers and their long rounded leaves.
Forager Friendly?
Yes, yes. Harvest responsibly. If this is invasive in your region be sure to take the entire plant (and root), and don’t plant the seeds. If it is not invasive in your region harvest with care.
Sources
https://en.wikipedia.org/wiki/Isatis_tinctoria
https://www.nps.gov/articles/dyers-woad.htm
https://www.youtube.com/watch?v=1TKLE62U1CQ
https://www.rhs.org.uk/plants/9409/isatis-tinctoria/details
https://agr.mt.gov/Topics/N-P/Noxious-Weeds-Pages/Task-Force-Pages/Dyers-Woad
https://www.ethnicjewelsmagazine.co.uk/articles-woad/
https://pmc.ncbi.nlm.nih.gov/articles/PMC7154893/
https://www.botanical.com/botanical/mgmh/w/woad--28.html
https://en.m.wikipedia.org/wiki/Mordant
https://molhort.biomedcentral.com/articles/10.1186/s43897-021-00021-w
https://www.cabi.org/projects/giving-dyers-woad-the-blues/
https://www.fs.usda.gov/database/feis/plants/forb/isatin/all.html
https://craftatlas.co/natural-dyes/woad
https://www.nwcb.wa.gov/weeds/dyers-woad
https://www.sciencedirect.com/science/article/abs/pii/S0378429006002395
https://herbnursery.co.za/mountainherb/herbinfo.php?id=359
https://localcolordyes.com/growing-woad/
https://www.botanic.cam.ac.uk/learning/trails/dyestrail/isatistinctoria/
https://www.sciencedirect.com/science/article/abs/pii/S0031942218307118
https://www.wearingwoad.com/the-woad-to-a-sustainable-blue-an-overview-of-woad-history/
https://thrumming.net/nevertheless-woad-persisted/
https://www.tekhelet.com/pdf/0905.pdf
The Woad Scrapbook could a tome, but here is a selection of random woad findings…
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