Purple can be one of the most frustrating colors in natural soapmaking.
For many soapmakers, that frustration begins with alkanet. They see photographs of beautiful lavender and violet soaps, prepare an infusion, and then end up with gray, blue, brown, or barely any color at all.
Alkanet is difficult enough that it can turn people away from botanical colorants entirely. But an unsuccessful batch does not mean botanicals cannot create beautiful purple soap.
Alkanet is simply particular.
The Key to Getting Purple Soap From Alkanet
The first key is using a high-quality botanical. I purchase my alkanet from Anne Georges, and the quality and freshness of your plant material can make an enormous difference.
The second key is preparing a strong infusion. A weak infusion may contain plenty of oil but not enough extracted pigment to create a noticeable purple in the finished soap. I share my specific infusion methods and ratios throughout my courses, but the larger lesson is that alkanet needs to be treated as a serious color infusion, not merely a lightly tinted oil.
Then you have to use enough of that infusion in your formulation.
Infusion rates can vary greatly depending on the botanical, the strength of the infusion, and the color you are trying to achieve. With alkanet, however, I do not recommend using less than 20% infused oil in the recipe.
Alkanet is also a pH indicator, and one of the best signs that your infusion is doing what it should is the wonderful color transformation that happens during soapmaking.
Your infused oil should have a rich grape-juice or mauve color. When the sodium hydroxide solution reaches the oils, the alkanet shifts to a striking blue in the high-pH soap batter. As the soap cures and the pH settles, that blue develops into the beautiful lavender or purple associated with alkanet soap.
Seeing that dramatic blue stage can be surprising the first time, but it is exactly the transformation you want to see.
Want to see that transformation happen in real time? Watch the full purple soapmaking class replay, where you can see the alkanet shift from its grape-colored infusion to blue in the fresh soap batter, then return to purple as the soap begins to cure.
Your soap formulation, gel phase, oil selection, botanical quality, infusion strength, and usage rate can all affect the finished result. Even when you work carefully, alkanet may still surprise you. That is part of its charm and, admittedly, part of why it can be so maddening.
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Alkanet Alternatives: What Is Anti-Alkanet?
Sometimes the best thing you can do with a frustrating botanical is set it aside for a while.
Natural purple soap does not begin and end with alkanet. There are other ways to explore the enormous range of colors we casually call purple.
Purple is not one specific shade. It is a loose term for colors that fall somewhere between red and blue. Purple can be lavender, violet, plum, berry, burgundy, mauve, smoky blue, or nearly brown. It can be bright or soft, pale or deep, warm or cool.
Once you stop searching for one single correct purple, the possibilities become much more interesting.
Color Blending Opens an Entire Purple Palette
Color blending is what really changed my relationship with natural soap colors.
It is also what led me to write The Natural Soap Color Palette and eventually become a botanical soap teacher here at Soapy Friends.
Instead of asking one plant to produce every color I wanted, I began exploring what happened when I combined natural reds and blues. A red-leaning botanical blended with indigo can create an entire progression of berry, wine, plum, violet, and deep purple shades.
You are no longer waiting for one temperamental botanical to cooperate. You are building the color yourself.
That does not mean every blend will be perfectly predictable. Natural colorants still interact with the formulation and continue changing as the soap cures. But blending gives you far more directions to explore.
During the purple lessons in the Natural Soap Rainbow, we combine Himalayan rhubarb and indigo to create a broad range of colors that could all reasonably be called purple. The goal is not to find one perfect shade. It is to understand how moving between red and blue creates an entire family of possibilities.
What Is Anti-Alkanet?
My anti-alkanet formulation came directly from my own frustration with traditional alkanet.
I could not consistently get the purple I wanted, so I began blending botanicals until I created my own alternative.
Despite the name, anti-alkanet is not another variety of alkanet. It is my botanical color blend designed to create purple soap without relying on a traditional alkanet infusion.
One of the things I appreciate most about anti-alkanet is that it can be prepared as a slurry. It does not need to sit in oil while an infusion develops, which means I can keep the dry blend on the shelf and make purple soap whenever I am ready.
Traditional alkanet and anti-alkanet do not create the same purple, and that is important.
Alkanet can produce a softer, cooler lavender-purple, while anti-alkanet gives me a deeper purple with its own distinct character. They are different colors with different preparation methods, and they complement one another beautifully.
The anti-alkanet formula I teach is the final balance I chose after extensive testing, but there is still plenty of room to experiment. Adding more madder root, for example, could shift the blend toward warmer, redder purples.
It can be used as a finished colorant, but it can also become the starting point for your own color exploration.
Purple Clay Is Another Option
Botanical infusions and color blends are not the only ways to create naturally colored purple soap.
Rainforest Chica’s Purple Clay is a wonderful addition to a natural soap color palette. Like all natural colorants, its finished appearance can shift depending on the recipe. A formulation high in shea butter, for example, may produce a warmer result than the dry clay initially suggests.
That variability is not a flaw. It is simply part of working with natural materials.
Rainforest Chica’s clays consistently give me beautiful, interesting colors, and the Intense Purple Clay offers another way to keep a ready-to-use purple on the shelf.
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Explore Natural Purple Soap Colors
Start with quality alkanet. Prepare a strong infusion. Use enough of it in your formulation, and watch for that remarkable shift from grape-colored oil to blue soap batter and, finally, to purple as the soap cures.
But do not let alkanet convince you that purple soap is out of reach.
Blend red and blue botanicals. Explore anti-alkanet. Try a naturally colored clay. Change the formulation and see how the color responds.
Inside the purple lessons of the Natural Soap Rainbow, we explore traditional alkanet, anti-alkanet, Rainforest Chica Intense Purple Clay, and color blending with Himalayan rhubarb and indigo.
You can also explore the complete Extracting Color from Nature series, my anti-alkanet masterclass, and The Natural Soap Color Palette for a deeper look at botanical color preparation and blending.
Explore the Natural Soap Rainbow
https://soapyfriends.com/courses/natural-soap-rainbow/
Explore the Extracting Color from Nature series
https://soapyfriends.com/product-tag/extracting-color-from-nature-soap-tutorials-and-master-classes/
Learn more about anti-alkanet
https://soapyfriends.com/product/anti-alkanet-master-class-live/
Become a Soapy Friends member
https://soapyfriends.com/membership/
Happy soaping 🧼
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