This blog post was originally written in 2011.  I am updating this to reflect my preferences that might have changed in the last 10 years.

These are my personal experiences and opinions.  I hope they save you time and effort.

Natural Indigo Powder

I have always been interested in unusual natural colors. This is what attracted me to adding natural Indigo powder in soap.
The color comes from the indigo plant, Indigofera. It’s native to India and is the oldest natural blue color known to man.  This blue Indigo was the original blue that was used to dye denim.

The powdered color is rich and dark blue to purple once it is harvested, fermented and then dried.

The Indigo powder I use is available from many Indian grocery stores or online.

Not all indigo powder is blue.  The leaves, before they are treated, are green.  The natural un-treated state of green indigo also makes a beautiful color for your soap.  Notice the soap on the table, one is blue indigo and the other is green indigo

Benefits of using Natural Indigo

Real Indigo color is not easy to find. In 1865 a German chemist, Adolf von Baeyer, produced a synthetic indigo. Most Indigo color comes from synthetic sources now because of the cost.

As a Reiki Master, I always look for ingredients that are attractive not just physically, but energetically.

Natural ingredients are always more beneficial as long as they are safe and ethically sourced.

I don’t expect the same results from synthetic colors and fragrances as I do from using natural ingredients.

I would compare it to having a home full of plastic plants compared to living plants.  There are no benefits to having plastic plants besides the low maintenance.

Indigo Powder Uses

There are so many great uses for indigo powder.  Cloth dying is probably the most popular use, but there are other ways to use this natural blue colorant.

Indigo powder for soap making is one way to use this interesting ingredient.

Using indigo powder to make self-care products such as bath salts and bath oils is another.

I’ve also enjoyed making natural indigo candles with indigo powder.

How to use Indigo Powder

Is indigo powder water soluble or oil soluble?

In other words, we need to know how to use indigo powder before we start our soap making or other products.

It’s always better to prepare our ingredients before we start creating our products.

I made a video showing you what happens when indigo powder and water are mixed together.

This video is showing us that water and indigo powder do not mix.  Indigo powder is not water soluble.

I made another video showing you what happens when indigo powder and oil are mixed together.

From this video we can see that indigo powder is oil soluble.  This is helpful to know so we can prepare our ingredients with this in mind.

Indigo Powder Soap

The best way to approach making blue powder soap is with a light hand.  Too much indigo powder in your soap can create a big mess around your sink.

Indigo powder soap will not have a scent unless you add a scent.

The powder on its own has a pleasant earthy smell similar to powdered beet root.

If your indigo powder has a strong sulphur smell, it has probably been treated to be used as a fabric dye.

I prefer the un-treated indigo powder for soap making and making self-care products.

How to use indigo powder in soap

Natural Indigo has antibacterial benefits and it’s a beautiful color when used in Soap Making and making self-care products.

I experimented with it for several years, using it in both cold process and hot process as well as natural liquid soap making. It turned out to be a very user friendly natural coloring that stays blue or green, even in cold process soap making.

Indigo Soap Recipes

Before making soap, please follow all safety precautions.

I feel it is my responsibility as a professional soap maker and teacher, to make you aware of Sodium Hydroxide

Sodium Hydroxide, which is your alkali for bar soap making, is caustic.  This means it will cause chemical burns on your skin if you don’t use safety measures.

Always wear gloves and eye protection.

This chemical is a class 8 dangerous good.

Sodium hydroxide is also known as Caustic Soda, Soda Lye, Sodium Hydrate, NaOH and Lye.

I have been working with sodium hydroxide for over 24 years and I am still nervous every time I use it.

Please approach this essential ingredient with respect and caution.  Mix your water and sodium hydroxide outside whenever possible since the fumes are also caustic to breathe in.

Here is a copy of my MSDS (Material Safety Data Sheet) from my supplier.

indigo blue vat blue

My company name is Mother Earth Creations which you can see at the top of each page.

Click here to see the MSDS for Sodium Hydroxide

Okay, now that I have made you aware of what you will be working with, we can move on.

How much indigo in soap?

An important question: How much indigo to add per pound of soap.

This depends on what you want to do with the indigo in your soap.

A swirl or a full colored soap bar?

In the Soap Making School Online Course you learn to create your own soap recipes with any type of oil, using a scientific formula that works every time.

I will be using a basic 2 pound soap recipe for this blog post.

Swirled Indigo Soap

Please note….. These are not full instructions, I do not recommend you make soap until you are shown how by an actual soap teacher.
12 ounces coconut oil
12 ounces olive oil
3.8 ounces sodium hydroxide
9.1 ounces purified or filtered water
2 ounces special oil (rice bran, grapeseed, jojoba, hemp seed, sweet almond, macadamia nut or whatever oil you prefer)
½ teaspoon indigo powder in a small cup
2 pound soap mold
Add 2 teaspoons of your special oil to the indigo powder. Mix it well with a small spoon until there is no powder on top or in chunks.
With a stick blender,
Link to stick blender post
mix your coconut, olive and the rest of your special oil together with your sodium hydroxide and water (Mixed separately, always adding the sodium hydroxide to the water and not the other way around – preferably doing this outside where you are not near anyone or any pets) remember this is a class 8 dangerous good.
Be careful and NEVER leave it unattended. The mixture is going to get up to 200 degrees F. It will take a while to cool down.
Depending on your weather, around ½ hour.
It shouldn’t be hotter than 120 degrees F when you mix it with your oils.
Bring your oils and alkali (sodium hydroxide/water) to a trace, add your indigo from your cup, stir lightly with a spatula not too much or the indigo won’t be a swirl.
Pour your soap into a 2 pound mold.
Cover and allow it 24 hours to Saponify (turn into soap).
For this entire time, your soap is still caustic. The tools you used are now dedicated to your soap making. Do not use them in your kitchen for food prep.
You can wear your gloves and wash your tools in a sink.
Spray vinegar in the area so your sodium hydroxide left behind will be neutralized.
Cut your soap after 24 hours.

Solid Indigo Soap

Please note….. These are not full instructions, I do not recommend you make soap until you are shown how by an actual soap teacher.
12 ounces coconut oil
12 ounces olive oil
3.8 ounces sodium hydroxide
9.1 ounces purified or filtered water
2 ounces special oil (rice bran, grapeseed, jojoba, hemp seed, sweet almond, macadamia nut or whatever oil you prefer)
1 teaspoon indigo powder
2 pound soap mold
With a stick blender,
Link to stick blender post
mix your coconut, olive and your special oil together and add the indigo powder.
Blend it well until all of the powder is dispersed into the oils. No floating clumps on top.
Add your sodium hydroxide and water (Mixed separately, always adding the sodium hydroxide to the water and not the other way around – preferably doing this outside where you are not near anyone or any pets) remember this is a class 8 dangerous good.
Be careful and NEVER leave it unattended. The mixture is going to get up to 200 degrees F. It will take a while to cool down. Depending on your weather, around ½ hour. It shouldn’t be hotter than 120 degrees F when you mix it with your oils.
Bring your oils and alkali (sodium hydroxide/water) to a trace (a thickness that creates a trail on top of your soap).
Pour your soap into a 2 pound mold.
Cover and allow it 24 hours to Saponify (turn into soap).
For this entire time, your soap is still caustic. The tools you used are now dedicated to your soap making. Do not use them in your kitchen for food prep.
You can wear your gloves and wash your tools in a sink.
Spray vinegar in the area so your sodium hydroxide left behind will be neutralized.
Cut your soap after 24 hours.

Indigo Powder in Self-Care Products

When you are using indigo powder in self-care products you need to be aware of its strong color and what the effects would be on your bath tub or sink.

Indigo Bath Salt

For every 100 grams of bath salt you make, add 1 gram of indigo powder.  Mix well and distribute the color through the salt.

Any salt you like works well for this.  I prefer equal parts of fine sea salt, medium ground Himalayan salt and coarse Epsom salt.

Indigo Bath Oil

For every 200 ml of oil you make, you can add 1 ml indigo powder.

Put most of the oil in your bottle.  Add your indigo powder. Place a lid on your bottle and shake it well.  Add the rest of the oil and shake it again until the color is uniform.

I prefer sweet almond oil, grapeseed oil, jojoba oil or rice bran as a bath oil.  You can use any oil you like or a combination of several.

I hope this information was helpful.  Using indigo powder in soap making and making self-care products can be a unique way to add a natural touch to your beautiful creations.

For more information on creating your own beautiful soap or self-care products, check out Soap Making School.

Indigo Blue Soap is the very first cold process soap that we take on in the Soap Making School Complete Course.

To you and your healthy skin