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Using Herbal Powders for Natural Colour in Soap

Using Herbal Powders for Natural Colour in Soap can challenge us beyond belief. It’s a real achievement to use an ingredient that you’ve grown or obtained from natural sources to make a beautiful colour combination, without resorting to a colour from a jar?

To help those that are interested in using natural colours for their products I’d like to offer a little help. These are the methods that I adopt in order to manipulate the ingredients that I would like to use.

Firstly, in order to save you a little time, it’s not hard to conduct a bit of research before you begin your project. I highly recommend using ‘Google’ as a starting point; just type in a basic question and see what you can find. Eg. How to make a cold process soap ‘pink’ naturally? You’ll be amazed at the information you’ll find, this of course allows you to read what others say and help you make your own informed decision before starting.

There are a few methods that one can adopt when using herbal powders to achieve great results, however each method will reveal a different effect and colour, some will be fantastic and others will not work out the way you intended at all, this of course is half the fun and always a learning kerb. Some herbal powders can be a beautiful pleasing colour to the eye, but when they are incorporated into your soap reveal colours that you don’t expect and are rather undesirable. To name a couple for you……Rose Petal Powder is a beautiful deep red/pink powder, in soap it’s brown. Beetroot Powder is a fantastic plum red, in soap it’s also a morbid brown. These are things that one learns pretty quickly and one might say, well….what’s the point? Although these herbs don’t offer a fantastic colour, they do impart precious properties that can be utilized to our advantage. These particular herbs may be best used in combination with something else?  Please conduct your own research about the benefits of using each herb in your product.

Remember to always record the exact steps that you’ve used to create your blend or infusion and label your jars/bottles accordingly, including the date that you have made it, for future reference. You’ll really want to know how you made it, so that you can do it again if needed.

Different herbal powders are suited to multiple methods, some better than others. There are three methods that I’d like to talk about in this post, Oil Infusions (Cold & Hot) and Water Based Infusions.

Water Based Infusion vs. Oil Based Infusion and remarkable results


Oil infusions are relatively simple to make and are widely used as a very easy inexpensive way to colour your soap naturally. Quite simply you can fill a jar with a liquid oil, like Olive Oil. Add into this jar a couple of tablespoons of your herbal powder, shake vigorously and allow it to sit for a few weeks. Eg. 250gm Olive Oil, with 25gm of Annatto Seeds, ground to a powder. Annatto Seeds offer a beautiful array of colours from pale yellow through to a deep dark orange, depending on the intensity of your infusion or amount used. Note that although your oil will take on the properties and colour of the herb used, it rarely offers a significant scent in our cold process soap that will last.

The method described above is a cold oil infusion, it allows the oil to take on the properties and the colour of the herbal powder that you’ve adopted.

How to Use a Cold Oil Infusion in your soap.

Using a portion of this cold oil infusion in your soap recipe is quite a simple process. The contents of the jar will settle to the bottom where it forms a sediment. This allows you to pour your oil from the top without disturbing the sediment that forms at the bottom. This avoids the need to strain out the sediment and avoids any spotting in your finished soap. If you happen to disturb the sediment you can strain it through some muslin in an endeavour to avoid incorporating the sediment into your soap. I’ve found that the sediment will result in your finished soap containing flecks of the herbal powder used. This gives you two options, pour from the top of the jar, or strain the contents before use to achieve a beautiful uniform colour that does not contain flecks. In some cases – the flecks can be attractive so it’s completely up to you.

Making a Hot Oil Infusion

This is also a prized method for many soap makers, it allows us to carry out the process quickly, with better results. So rather than doing a Cold Oil Infusion that takes anywhere from 3 weeks and more, you can carry out the exact same steps outlined above and heat the oil. Now I like this idea the most as this method forces the properties to release into the oil much quicker than if left do its own thing as in the cold method. Note that the heat forces the properties of the herbs out much quicker and better than if it’s just done with the cold method. I also recommend that you watch for the release of ‘colour’ when doing it, this ensures that you’ve done it right. So to make a hot oil infusion, place your oil of preference into a good solid canning jar and put this jar into a large pot containing water that you’ll bring to the boil, holding at a slow boil until you see a release of colour from your herb into the oil. Don’t walk away from your infusion whilst it’s boiling as you want to keep an eye on it for safety reasons. This is also an ideal method for those herbs that are what’s described as ‘woody’. Herbs that are ‘soft’ are suited to a cold infusion and herbs that are ‘woody’ are more suited to a hot oil infusion. To better describe this – ‘soft’ herbs are those that are florals like chamomile & calendula. They have soft petals. Herbs that are ‘woody’ like lemon myrtle, cinnamon, anise and hibiscus are more suited to a hot oil infusion. You’ll soon realise which method is best for which herb, trial and error is key. This is why we experiment to work out which method is best? Over time you’ll teach yourself and learn from peers. Once you know, you can then make a note of which way is best for your purpose. Of course there are many different ways that you can make hot oil infusions. This is just one way. I have also done this using my slow cooker, placing my jar in it whilst on the high setting. Just remember to ‘watch’ for the release of herbs. You can even do it in the oven. I encourage you to NOT put your oils and herbs directly into a pot on the stove, as your oil can overheat and be extraordinarily dangerous, catching fire. This would be a disaster.

How to Use a Hot Oil Infusion in your soap

The same applies as for a cold oil infusion. Simply replace the oil used in your soap, with your hot oil infusion either partially or completely depending on the intensity you’d like and carry on with your recipe as usual.

With either method described above, you’ll have created a beautiful natural soap that is coloured and infused with the properties of the herb used. How amazing is this? This can be carried out with the use of dried herbs that you’ve grown in your garden or with the use of herbal powders that you’ve purchased. Many of which you’ll find in your kitchen spice rack, others that are adored for the vivid pastel colours that they offer can be sourced from specialty herbal suppliers all over the world. If you’re in Australia, make sure you check out the selection that can be purchased from my online store.


Some herbs are better suited to being used as an oil infusion and some are much better used in a water based infusion, rather like a tea. Why is this? If the herbal powder emulsifies in water, chances are it will be best used in a water based infusion, much like a tea. If the herbal powder clumps together when placed into water and won’t mix in, it’s probably going to emulsify much better in an oil infusion. It’s either one or the other and not hard to experiment to work out which is which. However, sometimes it actually comes down to trial and error. Whilst some will definitely mix in both water and oil, when you make your soap and it cures – you’ll notice very quickly which method offers you the best colour. It’s amazing and sometimes not until the finished result is revealed that you can decide which method you’d like to adopt.

How make a water based infusion?

I certainly like to employ the use of heat with this method as it’s just invaluable. Just like you’d make a cup of tea, boil your kettle and make a cup of your chosen brew, allowing it to steep in the hot water to release all its glory.

How to use a water based infusion

Strain it using whatever you have on hand or add it straight depending on your desired result. Just as I’ve previously stated; if strained, you’re removing the herb or powder to reveal a coloured and infused water. If left unstrained you’re going to include the herb or powder in your finished soap which can be a desired trait in some instances but the majority of time its best used strained. Tea Strainers work wonders as does a piece of muslin or jute, even coffee filters work a treat to strain your brew.

Water based infusions work a treat with ‘soft’ herbs and powders, I’ve also had great success using ground resins, oats, salt, coffee and the list goes on and on. This water can be used as your lye liquid. I’ll also just mention that many of these ingredients can be added directly to your hot lye liquid after it’s just mixed. Right after you add your Caustic Soda (Sodium Hydroxide) to your water, it will naturally gain tremendous heat, at this point; gently place your ground powder directly into the mix and gently stir, making sure you are wearing the appropriate safety apparatus for the job at hand. The heat of the lye will incorporate your additive perfectly, then you can simply pour your lye through a sieve and into your oils and continue with the process of making your soap.

This is very simple and once you’ve done it this way, you’ll probably do it all the time. This method works really well for your ground oats and coffee, salt and other water based herbal powders like parsley powder and indigo. You can even use cosmetic clay’s this way. In terms of how much dried matter to add, it’s really up to you, try start out by adding a heaped tablespoon of ground oats or salt and see what this does for your soap? Note that if you’re using a coloured ingredient like green or pink clay, the entire soap is going to be this colour as it will be distributed through the whole soap.

A few of my tips to help you get started…..

Clay – is a water based ingredient and can be put into your lye water or added to your soap at trace
Indigo Powder – is water based and makes beautiful shades of blue
Annatto Seeds – are oil based, making beautiful shades of yellow through to orange
Alkanet Powder – is oil based, making beautiful shades of purple
Madder Root Powder – can be used as either a water based infusion or oil based and produces all shades of pink through to deep red
Parsley Powder – is best infused in water and produces very pretty shades of lime green
Coffee Grounds – are best infused in water and produce all shades of cream to brown
Spirulina Powder – I’ve achieved great results in water & oil, producing striking deep green
Charcoal Powder – is water based, producing all shades of grey through to black
Ground Oats – water based, best dissolved in lye water and produces lovely creamy results in your soap
Ground Resins – water based, best dissolved in lye water and builds on the properties found in your soap
Salt – water based, best dissolved in water and assists to harden your soap, offers antibacterial properties (best known as brine soap)
Paprika Powder – oil & water based, I’ve achieved best results in a hot oil infusion offering spectacular shades of orange colour to your soap
Turmeric Powder – oil & water based, I’ve achieved best results in a hot oil infusion, all shades of yellow
Chlorella – water based, all shades of green

Here’s a video where I describe a really simple way to Make an Oil Infusion and use it in your soap.  I use the olive oil to make the infusion prior to using it in my soap.  It’s really simple.  Using herbal powders for natural colour in soap is a very rewarding process that you’ll embrace, allowing you to create a unique and timeless product for all to enjoy.

I hope you enjoy making some amazing soap with the information that I’ve provided, if you’ve any questions please don’t hesitate to send a message using the contact form on the website.