Indigo is a natural dye extracted from a plant. Not only is it one of the oldest natural dyes used for coloring wool and fabric, it's also the original dye used for shibori.
In this tutorial, you'll learn how to prepare your own vat of natural indigo, which is the first step to creating beautiful shibori or tie-dye designs.
20g of pre-reduced indigo, 250g of reducing agent (thiox or hydrosulfate) and 250g of soda ash, which you can find in this indigo dye kit.
19L (5 gallon) plastic bucket with a lid
Stick for stirring (make sure it's long enough to reach the bottom of your bucket)
Small container for the "flower"
Sheet of plastic to cover the floor
Shallow pan to hold your fabric
1. Set Up the Indigo Vat
It's best to work outdoors, if possible, because things can get messy and you're working with dye. Put down a sheet of plastic to cover the surface you're working on. Make sure you wear protective gloves and an apron as well, so that you don't end up looking like a smurf!
If you use the whole kit, you should have sufficient dye to color up to 15 natural-fibre T-shirts or 15 metres (15 yards) of fabric. If you wish to work on a smaller project, you can use a smaller bucket with half the water and half of the dye's ingredients. In this tutorial, I'll guide you through the quantities for preparing the whole amount in the kit.
First, add 15 litres (4 gallons) of warm tap water to a 19 litres (5 gallon) container, which is not used for food. You can use a smaller container with measurements to calculate the water quantity.
Empty the entire container of pre-reduced indigo dye into the bucket.
With your stick, stir gently towards one direction until the indigo dye is dissolved in the water.
While stirring, carefully empty the soda ash and the reduction agent into the water.
Continue to stir gently but thoroughly. Always stir in one direction with a circular motion. Once you feel the dye is properly mixed, slow down. Now, reverse the direction of your stirring, while dragging the stick towards the outer edge of the bucket. Then slowly remove the stick from the dye.
Cover the bucket with a lid and let the dye settle from 15 minutes to one hour, which is the optimum length of time.
2. Dye the Fabric
While waiting for your indigo vat to settle, you have enough time to prepare your fabric for dyeing. Keep in mind that the natural indigo dye is suitable only for natural fabric such as 100 per cent cotton, linen, rayon, and hemp.
At this point you should choose which pattern you wish to create, and fold, tie or bind your fabric by following one of my tutorials in the shibori series. The patterns are basically created by blocking color from certain parts of the fabric, which remain white.
When your fabric is tied, thoroughly soak it in water and squeeze the excess water and air out of it. Now it's ready for the next step.
Once the vat has settled, remove the lid.
You will notice that the top of the dye bath is covered with a layer of foam. This is called the "flower" or "bloom". Push the flower gently aside and check that the color of your dye is clear yellow or yellow-green. If not, you need to let the dye bath settle for about another half hour.
(Please note that in the first image below, the dye looks blue from the top because of the layer of foam/flower. You can see the clear yellow/yellow-green color in the second photo below - on the right side where the sun is shining. It looks darker on the left side because of the shadow on the bucket.)
Once the dye bath has turned the desired color (as per the instructions in your dye kit), you are ready to start dyeing.
Make sure your gloves are on first, then use the smaller container to scoop the foam/"flower" from the top of the vat and set it aside. Don't throw it away, as you will need to place it back once you've dyed your fabric.
Continue to squeeze your fabric as you slowly submerge it into the vat.
Once it's submerged in the dye, gently move the fabric around to make sure that all the unbound parts are dyed evenly. You don't need to leave it in the dye for very long. One to several minutes will be enough.
Just be careful not to drop your fabric in the vat, as it will probably fall to the bottom where the residue has settled. If you stir this up it may cause spots on your fabric.
3. Allow to Oxidize, then Untie, Rinse and Dry
Gently remove your bound fabric from the dye bath. Avoid splashing or dripping into the vat, as this introduces oxygen back into the dye. Put the lid back on the bucket to keep it as oxygen-free as possible.
As you can see, the fabric looks green when you first take it out of the bucket.
This is when the magic happens (or to be more precise, chemistry). Indigo develops its color when it is exposed to oxygen. Once the fabric is in contact with the air, it starts changing color and turns from green to blue.
Place the fabric into the empty shallow pan and leave it there to completely oxidize and turn dark blue. This will take about 20 minutes. If necessary, turn the piece over and open up any areas that need to be in contact with the air to be colored.
If you wish to achieve darker shades of blue, you can repeat the dyeing process and re-submerge the fabric into the vat.
If you're happy with the color, rinse your piece of bound fabric in warm water. Then untie the fabric and hand wash it with mild detergent in warm water. Just be aware that your fabric will look darker at this stage, and the final color will only emerge once the fabric is dry. Leave the fabric to dry in the shade.
If you have finished with your dyeing session, gently place the foam/"flower" back onto the surface of the dye and centre it by repeating the stirring process as before (stirring in one direction first, then reversing the direction and stirring until the flower is in the centre of the bucket).
Remove the stick from the vat and carefully place the lid on the bucket to close. Allow the dye to settle for at least an hour before starting another dyeing session.
The vat can keep for several days and you can dye several times. Just keep it at a comfortable room temperature. Once you are ready to dispose of the vat, empty the contents down the drain and clean up the container and the stick with soap.
Warning! Keep out of reach of children and animals. These substances (natural indigo dye, sodium carbonate and thiourea dioxide or hydrosulfate) may be harmful if misused. Read instructions and cautions on the product packaging carefully before use.
Ready, Steady, Indigo!
Now you know exactly how to dye fabric with natural indigo, you're ready for some shibori fun.