In this blog post and video, I am demonstrating how I extract indigo from the leaves of the indigo plants I grow in my dye garden. I want to emphasize that I am not an expert or master at this craft. This is an ancient craft that many cultures have honed, developed, and mastered over millennia. There are many different methods for extraction. Today, many indigo dye artisans have far more expertise, craft, and knowledge than I do. I learned everything you see here, in much greater detail, from a course taught by The Dogwood Dyer. Here on my blog, I simply want to share with you my experience and what I’ve learned in my short time with this amazing natural dye.
Enchanted by Natural Dyes
Learning how to grow and use natural dyes for my fiber art practice is a lifelong, ongoing goal of mine. As a teen I loved using RIT Dye and bleach to revamp all kinds of clothes and fabrics. I was (and still am) really into upcycling and using found/thrifted fabrics to sew into new creations. Several years ago, I discovered natural dyes, and I was hit with an intense longing. You know how some crafts just call out to you? This was natural dye for me. I’ve always felt a strong connection to the earth, flowers, trees, animals, etc. The idea that I could harvest and use plants for color in my sewing was enchanting.
I didn’t start right away, but read some books and watched some videos on natural dye. But after a year or so, I bought an indigo dye kit and set up my first indigo vat and dyed some fabric. It was easy and a huge success. I was immediately hooked. Shortly after that, I learned how to use other natural dyes and began dyeing raw wool, silk, and angora. Last summer, I grew my first dye plant: Indigo.
This year, I grew even more, along with coreopsis, a dye flower. Both have been flourishing, and recently I’ve been extracting indigo pigment from my indigo plants. Extracting indigo is a multi-day process that I enjoy from beginning to end.
How to Extract Indigo From Leaves:
Ferment the indigo leaves
1. Once your indigo plants are about 2-3 feet tall, cut them down to about 8-10″ tall. Just make sure they still have leaves/nodes on the remaining stalks.
2. Immediately put cut stalks into a plastic bin with water. Weigh the stalks down, cover, and ferment for about 24 hours, until the water is aqua blue and the smell is sickly sweet. The time can vary based on how hot the ambient temperature is, and how hot the water you used is.
3. When the water is aqua blue and smells sickly sweet, immediately remove all plant matter from the water. At this point, the indigotin chemical has been extracted from the indigo leaves and is in the water. If you wait too long to remove the plant matter from the water, the indigo will over ferment, which destroys the indigotin pigment. If the plants are slimy and brown, and the bin smells rotten, they have over fermented.
Alkalize
4. Once all plant matter is removed, add pickling lime to the aqua water a little at a time. This will increase PH to about 10 or 11. Add the lime gradually, stirring well and checking the PH with each addition.
Oxidize
5. When a PH of 10 or 11 has been achieved, immediately stir and froth the mixture to aerate and oxidize. I use a metal rake. You can use a whisk, paint stirrer, pump, or simply pour the liquid from one bucket to another. As you froth the liquid, you introduce oxygen, and the aqua color changes to deep blue. This process requires 5-20 minutes of stirring and frothing, depending on the efficiency of your method.
Let it settle
6. When the mixture is deep blue and the bubbles seem to dissipate quickly, cover and let the pigment settle to the bottom. This whole process of adding lime and oxidizing creates a bond between the indigotin chemical in the water and the particles of lime. Once the indigotin binds to the lime, it becomes heavy and sinks to the bottom of the container. Settling takes several hours or up to a day or two. Fill a glass jar with the liquid and bring it into the house so you can watch it settle and see when it’s done.
Pour off liquid
7. Once the pigment is settled on the bottom of your container, you will see dark blue granules at the bottom, and clear/yellowish water a the top. Carefully pour off as much clear/yellow liquid as possible, without disturbing the pigment granules. When you can’t pour or scoop off any more, strain the remaining liquid and pigment. I use a fine micron bucket strainer, but you can use a coffee filter or a piece of finely woven fabric, such as a silk scarf, placed over a mesh strainer. Catch the liquid in a bucket -it is alkaline and shouldn’t be dumped anywhere until you mix in some vinegar and achieve a neutral PH.
Let it dry
8. When your pigment is fully strained out of the liquid, leave it on your strainer to dry into a powder.
9. When fully dry, crush indigo pigment and store in a jar. Begin planning your upcoming indigo dye vat!
Repeat!
10. Repeat steps 1-9 when your indigo plants have grown back about 12″ or more. This took my plants one month. They are very happy plants, loving the heat and humidity of Louisiana. Bunny poop fertilizer helps too!
Extracting Indigo: A Plant Lover’s Dream Project
All that work extracting indigo those beautiful green leaves, and I haven’t even started dyeing yet. But to me, extracting indigo pigment is just as fun as dyeing wool. I love working with raw materials -the rawer, the better. That’s why I felt drawn to natural dyes. Give me plants and flowers to play with! I would much rather handle those than chemical dye powders -it’s much more fun.
Indigo In the Shop
I exclusively use natural dyes in my shop. I regularly use indigo to dye fiber for making batts for hand spinners. Occasionally I dye fabric, bandannas, or yarn to use in weaving and knitting. It’s important to me that my batts and other products I sell always have close ties to the earth, and a strong human touch. Click below to purchase an indigo dyed product from my shop!
Really enjoyed watching this. I learned a lot and can’t wait to do it myself.