Natural Lavender Soap Recipe (Cold Process)
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Full instructions for how to make lavender soap from scratch using essential oil and alkanet root, a natural purple soap colorant. You begin by extracting the natural dye from this plant into olive oil, then using the ruby-red oil to make purple soap!
Lavender is a beautifully scented flower that’s also great for the skin. It can help clear acne and calm eczema, and lavender essential oil is also known to help speed the healing of wounds and burns. Over the years, I’ve created and shared recipes for various types of lavender soap.
Some of them include a blend of essential oils, while others have added exfoliants, flowers, or natural soap colorants. The lavender soap recipe I share in this piece is, by comparison, pure and simple. It’s a single, beautiful color and uses just one fragrance—lavender essential oil. I show how to make it with common soapmaking oils and a natural purple soap colorant called alkanet.
There are many ways to make lavender soap, though. Generally, it’s accepted as lavender-scented soap. Sometimes, that scent is natural, and sometimes, synthetic perfumes are used. Other ways to make lavender soap include using homemade lavender-infused oil or lavender flower tea and decorating it with lavender flowers. I’ll go over each of these before we head into making this natural lavender soap recipe.
New to Making Soap?
If you’re new to making handmade soap, I recommend enrolling in the online natural soapmaking for beginners course. It gives a good introduction to what to expect from ingredients, equipment, and soap recipes, as well as how to make soap. It’s especially important to be careful when handling lye, and you should follow soapmaking safety guidelines when making handmade soap.
Lavender Essential Oil for Soapmaking
Lavender soap is generally understood to smell like lavender. The real deal is always made with lavender essential oil, which is the volatile oil extracted from lavender flowers. It’s deeply fragrant and has more benefits for the mind and body than I can list here.
You can even grow English lavender to use in soap and skincare recipes; however, making essential oil is a whole other ballgame. It needs to be extracted using a steam distiller, and you’ll need about 3 pounds (1.36 kg) of lavender flowers to produce just 15 ml of essential oil. That’s why most soapmakers buy essential oils.
When sourcing lavender oil for soap recipes, also be aware that there are two main types of essential oils. Lavender flower oil labeled Lavandula angustifolia (English lavender) flower oil is the more common and the type I recommend. The second is distilled from a similar plant, Lavandula latifolia, and is more commonly known as lavender spike oil. It smells like lavender but has a touch of camphor and herbaceousness.
How Much Lavender Essential Oil to Use
The homemade lavender soap recipe below already includes an amount of essential oil, and it’s moderate at just 3% of the recipe. Even though you’ll see other recipes call for more, it’s best to stick to that essential oil rate until you can work out the specifics of the product you’re using.
That’s because not all essential oils are the same, and allergen levels can vary from manufacturer to manufacturer. It’s a bit of math and finding the right documentation for the specific essential oil you use. Sometimes, it’s listed in a general PDF for all the essential oils a company manufactures. Sometimes, it’s in a separate allergens declaration document.
The amount you use in soap is dictated by the levels of these 26 natural substances found in essential oils. That’s because if you include too much of them, your soap can cause allergic reactions in some people. The current main allergens to be vigilant of in lavender essential oils are geraniol, limonene, and linalool. The European Union is currently planning to add 56 other substances to this list, so, at least in Europe, the legal usage rate for lavender essential oil in soap recipes may change.
Lavender-Infused Oil in Soap Recipes
There’s another type of lavender oil that you can use in soapmaking, too, but it’s not an essential oil. Homemade lavender oil is a liquid infused with lavender flowers, and though it won’t scent your soap, it can be a way to include homegrown lavender in your soap recipes.
To use it, replace the oil called for in the recipe with the same oil that you’ve infused with lavender. For example, you could replace all of the olive oil in a soap recipe with lavender-infused olive oil. This castile soap recipe is made with 100% olive oil, so you can replace it entirely with lavender-infused oil if you wish.
Lavender Tea in Soapmaking
Another way to use lavender in soap recipes is to substitute the water called for with lavender tea. It doesn’t add scent or any real properties, but it can, again, add a special-to-you element to your soap recipe. It can also tint your soap a light beige, which is a nice effect.
To make lavender tea for soap recipes, heat about 5% more distilled water than the recipe calls for. Heat it to scalding hot, then for every cup (237 ml) of water, add 1 teaspoon of dried lavender buds or 2 teaspoons of fresh. Let steep until the liquid reaches room temperature, then strain the lavender from the water and measure the water to the amount called for in the recipe. Make the lye solution with the lavender tea as usual.
Alkanet Soap Recipe
Aside from the subtle color lavender tea may impart to your soap, lavender itself won’t naturally color soap recipes. Especially not blue or purple. You can, of course, leave the soap its natural creamy color, but it’s fun to match the soap’s color with the scent. I’ll show you how to do this later on using alkanet root (Alkanna tinctoria), a natural purple soap colorant.
The process begins by infusing the roots in liquid oil, then using that oil in the soap recipe. I recommend that at least 30% of the oils in an alkanet soap recipe are infused with alkanet. This recipe includes fifty percent, which gives a really deep and lovely color. The infused oil is also about six months old, so the color is more intense. With alkanet, you can get various shades of earthy purple, from quite light to very dark.
Sourcing Alkanet Root for Soapmaking
Alkanet is a common dye plant mainly wild-harvested in south-eastern Europe, India, and Pakistan. Many soapmaking suppliers stock it, and it comes as a powder or chips of dried roots. There’s a lot of color potential in the smallest amount! I highly recommend buying alkanet from a trusted soap-ingredient supplier. Many online sellers label a similar plant, ratanjot (Arnebia nobilis), as alkanet. It looks similar, but it will not give you a lovely purple color. I’ve accidentally used it before, and it turned my soap gray.
The alkanet I use in soapmaking comes from a UK company called Summer Naturals, but there are other good sources. When alkanet root arrives, it’s usually in a clear plastic bag, and if the inside of that bag has a vibrant purple residue, you can trust it to make naturally purple soap. If you don’t notice it, then the quality might not be good enough. Test it, though, with a small batch like the lavender soap recipe below, just to make sure.
Naturally Coloring Soap Purple
Aside from alkanet root, gromwell root (Lithospermum erythrorhizon) is another excellent natural soap colorant. You use it the same way as alkanet, as an infused oil. Brazilian purple clay is popular, too, though it can give a more earthy purple color, as most clay soap colorants do. Infusing whole cannabis plants in a carrier oil and using it in soapmaking can also give a light purple color, though I’ve not tried this. Mixing indigo and madder may also give a lavender-like hue.
Ultramarine purple mineral powder is also popular in the soapmaking community for its stable and vibrant color. It’s not considered natural but rather a natural mineral pigment. The purple it gives is much more conventional—clean, bright, and quite lovely in its own right. I used half a teaspoon of mineral powder per 1 lb (454 g) soap batch to achieve the color shown above.
Using Lavender Flowers in Soap
If there’s one way to communicate that it’s lavender soap immediately, it’s by decorating bars with lavender buds or flowers. There’s just one major issue with using them in soap: they tend to turn brown wherever they come into contact with the soap.
Mix them into your soap batter, and they will definitely turn brown. Sprinkle them on top, and they’ll probably turn brown. And if you’ve ever had mice in the house and seen what they leave behind them, you’ll realize why mixing lavender buds into soap is a bad idea. The connotation between mouse droppings and your lovingly made product is not a good one!
There are two tricks to prevent lavender from turning brown in your soap, though. The more lavender buds that don’t touch the soap or only touch it minimally, the less browning you’ll see. The first one uses dried lavender buds still attached to the flower stalk. If you lightly press them into your soap about 5 minutes after you pour it, you can get away with just the slightest browning.
Make sure only the bottom edge touches the soap, though. It also helps to use darker lavender varieties, such as ‘Hidcote.’ They’re so deeply colored that you don’t notice as much color changing, and they stay beautiful for months on end. All the more reason to grow lavender at home.
Stick Lavender on Soap with Rubbing Alcohol
The other method for preventing lavender from turning brown in soap involves sticking it to soap that’s already hardened. What I do is pour lavender soap batter into molds and allow it to sit for 24-48 hours. Then I pop the soap out of the molds and cut them into bars. Next, I’ll spray the tops with rubbing alcohol, sprinkle lavender buds on top, and spray them again.
As the alcohol evaporates, the lavender will stick to the soap. Although lavender can naturally brown over time, it will take weeks or months to see this with this method.
More Lavender Recipes
- How to Make Lavender Bath Bombs
- Lavender & Honey Cookie Recipe (so good!)
- Lavender Body Balm Recipe
- Blueberry & Lavender Jam Recipe
Lavender Soap Recipe
Equipment
Materials
Alkanet-infused oil
- 1/8 cup alkanet root 2 TBSP / 11 g / 0.39 oz
- 275 g olive oil (light colored or pomace) 2.65 oz – or light-colored olive oil
Lye solution
- 63 g sodium hydroxide 2.22 oz
- 126 g distilled water 4.44 oz
Solid oils
- 114 g coconut oil (refined) 4.01 oz (25%)
- 91 g shea butter (refined) 3.21 oz (20%)
Liquid oils
- 227 g alkanet-infused olive oil 8.02 oz (50%)
- 23 g castor oil 0.8 oz (5%)
Add after Trace
- 3 tsp lavender essential oil 13.6g / 0.48 oz
- 5 dried lavender stems (optional)
Instructions
Make the alkanet-infused oil
- At least 1 month before making soap, mix the alkanet root with the olive oil in a mason jar and leave it in a dark, but warm place to infuse. Shake the jar every couple of days, and you'll get a good color extraction after a month. If you can wait longer, the color will be much deeper*. Up to a year for good, deep color. Keep an eye on the oil's best-by date if you plan to do a longer infusion period *
- Strain the infused oil through a sieve lined with cheesecloth. This double layer will help ensure that tiny alkanet pieces don't pass through. A few small ones are okay, if that happens, but alkanet can feel scratchy in soap, so try to avoid having pieces make their way through.
- Measure the amount of alkanet-infused oil needed for the soap recipe. You may have a little leftover that you can save for another batch.
Preparation
- Cold-process soapmaking is chemistry, and this recipe uses lye. Lye is a caustic substance that is completely neutralized in the soapmaking process, but it can be harmful if not handled correctly. Please read this soap making safety guidance before proceeding.
- Set out the equipment you need and measure out the ingredients before starting to make soap. The distilled water should be in a heat-proof jug, the sodium hydroxide in another jug, and the solid oils in a pan. The infused oil and castor oil can be in another jug, and the lavender essential oil in a glass ramekin.
- You should also be wearing closed-toe shoes, long pants or skirt, long sleeves, and have your hair pulled back. Wear safety goggles and gloves.
Mix the Lye Solution
- Work in an airy place, such as near an open window, and pour the sodium hydroxide into the water and stir well. There will be heat and steam, so be careful and avoid inhaling it. Leave the jug of lye solution to cool in a sink filled shallowly with cold water.
Melt the Solid oils
- Place the pan of oil over low heat, and stir and break the pieces up to speed up melting. When only a few small unmelted pieces remain, take the pan off the heat and continue stirring on the side.
- When fully melted, pour the liquid oils into the pan: the alkanet-infused olive oil and the castor oil. Save the essential oil for later. One tip for reducing air bubbles in your final soap bars is to pour the liquid oils against a spatula or immersion blender placed in the pan. It helps the liquid oils to flow in rather than splash in. Air bubbles aren't necessarily bad, just something that soapmakers try to avoid for aesthetic reasons.
Taking the temperature
- When making this small soap recipe, aim to cool both the oils and lye solution to around 110-120°F (43-49°C). An infrared thermometer makes quick work of this task, but a digital or glass thermometer works too.
Immersion blending
- When the temperatures are around 110-120°F (43-49°C), pour the lye solution into the pan of oils through a sieve. It will catch any bits of undissolved lye.
- Next, dip the stick blender into the pan and press it to the bottom. With it turned off, stir the mixture, keeping the immersion blender's head against the bottom. Next, bring it to the center of the pan, still pressing down, and blitz it for just a couple of seconds. Turn it off and stir the soap batter, using the blender as a spoon.
- Repeat until the mixture thickens up to a light 'trace'. This is when the batter leaves a distinguishable trail on the surface. The consistency will be like thin custard. The batter may look gray, purple, or blue at this point.
Essential oils & molding
- Now, at light trace, pour in the essential oil. Stir it in quickly but thoroughly. You will notice the soap getting thicker as time goes on, and you'll probably be at medium trace now—more like a thick pudding in consistency.
- Once the essential oil is fully mixed in, pour the soap batter into the mold(s). It should fill up the 1-lb loaf mold well but have a heaping top. That's fine, and what I've done here is create swirls on top with a skewer. Just use small circular motions up and down the soap. This is optional, though, and you can use whatever texture or non-texture you'd like.
- Another optional step is decorating the tops of the bars with lavender flower heads. I've only lightly pressed them in, being mindful that the buds will turn brown anywhere they touch the soap. I've placed them so that one flower head will be at the top of each bar of soap.
Cure the Lavender Soap
- Once the soap is in the mold, it helps to force the soap into gel phase. This is a period of prolonged, but gentle heat that can deepen the soap's color. It's always a good idea to do with alkanet soap recipes. There are two main ways to go about this: the first is to wrap the soap mold in a towel, protecting the top surface of the soap with cling film, and leaving it overnight.
- The second way is to oven process it, which is very easy. Heat the oven to 170°F (77°C) and place the soap inside. You can set the mold on a square of baking paper or cardboard, if you wish. Turn off the oven, close the oven door, and leave the soap in for twelve hours or overnight.
- You have the option to pop the soap out of the mold and cut it into bars immediately or wait 2 days. Waiting two days is safer since the lye used in the recipe will have fully transformed into soap.
- Wear gloves and cut the soap into bars with a soap cutter or sharp knife. After this, cure the soap for four to six weeks before using it. The purple color will fully develop during this time, and depending on the strength of the alkanet and how long it was infused into the olive oil, the bars range from light to dark purple.
- To cure the soap, place the bars in an airy but dim place with plenty of airflow. Leave them there, undisturbed, for at least four weeks before using them. You should also store handmade lavender soap in an open, dim, and airy place. Doing this helps keep the soap dry and in good condition for years.
After reading through the comments, I’m assuming that you changed the recipe for this soap at some point, since some commenters mention palm oil and sunflower oil. Are the soap photos of the original recipe, or the revised one? I’m asking because I made this soap for the first time this weekend, and the color is much grayer than the photos included with this recipe. I infused a light colored olive oil with alkanet for three months to obtain the color. The only alteration I made was to substitute 10% cocoa butter for some of the shea butter (I ran it through soap calc first, of course). I used CPOP to try to insure deeper color, and my soap was fully gelled. I’m thinking the color may be off due to the shea butter? It was not white refined shea, but a slightly yellow, raw shea. Any tips for getting a more purple soap using alkanet?
Hi Heather, the recipe and photos correspond. The issue you’re having has to do with the alkanet you’re using and it’s one I’ve encountered many times. There’s a similar plant called ratanjot that’s often sold as dyers alkanet and though it looks the same, the color in soap is poor. Where did you buy your alkanet from?
I purchased it on Amazon, which I know can be iffy. The supplier was mGanna, supposedly 100% alkanna tinctoria root powder, and it specifically mentioned soap making. A reviewer claimed that it produced amazing purple in their cold-process soap, so it seemed legitimate. It did make a lovely ruby-colored infusion in my olive oil. I’m wondering if I would get better results using “whiter” oils. I hate to waste materials and time.
This recipe and oil choices are tried and tested and it’s similar to how I make my commercial lavender soap. Ruby red infused oil is a good sign, but if you have a gray color after gelling, that can be a sign of poor quality plant material. I’d try with another supplier of alkanet. Personally, I think the best alkanet comes from natural dye supply shops rather than soap making ingredients suppliers. They simply won’t mess around with poor quality dyer’s alkanet. The only downside is that alkanet from dye supply shops won’t come with skincare documentation so it’s tricky to use their product in making soap for the UK/EU market. There’s a lot less regulation in the US, though, so you can probably get away with using it, even for commercial soapmaking. I get dye ingredients from a company called the Wonky Weaver in the UK. There are loads more options across the pond.
Thank you so much for your prompt replies and your input. I’m new to cold process soaping, and your site is a teasure trove of information! I will look for a supplier among dye shops, or possibly Etsy. In the mean time, I have some leftover infused oil. I might as well play around with it. Maybe I will try it with coconut oil in a small batch.
You’re most welcome and good luck!
It has taken me a while, but I finally re-tried the alaknet infusion in my soap. I ordered alkanet powder from Brambleberry and infused the oil for three months. I had much better results with the new alkanet powder. I got a lovely soft lavender color. Thank you for your advice.
You are most welcome, Heather :) Having quality alkanet root can make all the difference!
Dear Tanya. Do you ever have a day course that people can come and have a face to face with you?
All the best
Hi Wendy, yes I do! There’s one place left in November’s Natural Soapmaking Workshop if you’d like to join.
The coconut oil I have is a linguist vs. solid. Will this work with your lavendar soap recipe? Also, can I grind dried lavender flowers and add to the soap? Thank you for this most informative article!
Hi Janet, is the coconut oil liquid because it’s summer and a warm ambient temperature? If so, yes you can use it. If it’s liquid coconut oil, also called fractionated coconut oil, then it’s not suitable for the coconut oil in this soap recipe. Yes you can add ground lavender flowers to the tops, though :)
Hi , for the Alkanet infused oil
Should be counted for a total of 8.02 Oz ? Mix infused oil with the other olive oil to equal 8.02 total ? Thank you !
Hi Ruth, all the olive oil you use for making this recipe is infused with alkanet. I’ve updated the recipe card to be more clear!
Thank you !!!
I can’t to make this but don’t have any palm oil! Can I substitute it with something else?
Hi Susie, you can directly substitute tallow (cleaned beef fat). However, you can use the soap additives in this recipe (alkanet, lavender eo) such as this eco-friendly soap recipe.
That’s great. Thank you Tanya
Me gustan mucho tus recetas. Good job!!!
Love💜 the colour of the Purple Lavender soap.
How would this work for hp soap?
~Cheers
~Wanda
I’ve not tried it yet but I have no doubt that it would work a treat :)
Oooops, forgot to ask if the Sunflower oil is high oleic , mid oleic or a linoleic sunflower oil?
THANK YOU,
Catherine
You can use any type of sunflower oil for this recipe – it won’t affect the amount of lye needed. I’ve used standard sunflower oil that is not labeled with a linoleic profile, meaning it’s likely a medium level. The fatty acid profile will change a bit if you use high-oleic sunflower oil, though. Linoleic and oleic, especially, which means that your bars could be more conditioning and have silkier lather. They may also be more prone to DOS.
Hi Tanya/Lovely Greens’
This is Catherine. New to soap making. Is the palm oil used in the lavender soap a palm kernel oil or a palm liquid oil? My apologies, have never worked with palm. Are certain palm oils liquid and others solid?, and which one is used in the above recipe?
Thank you, sincerely
Catherine
Hi Catherine, stick with standard palm oil, which comes as a solid white fat. Try to find sustainable palm oil, though, because a lot of palm oil is dirty and destructive to rainforests. There’s also palm kernel oil and red palm oil that can be used in soapmaking. They all come from the fruit/seeds of the same plant, Elaeis guineensis, but are extracted and processed differently.
So many soap groups are adamant that lavender will “mold” and that it is dangerous to use the buds and should NEVER be used, or maybe sprinkled. I find this attitude ridiculous, as many soapmakers even in retail stores, use lavender buds all throughout their soap, the buds are brown, but I highly doubt they are “moldy” or “gone bad”, they are just discolored. What do you think?
Lavender buds don’t mold for me on or in soap, but I don’t live in a hot and humid place. Those that do have reported dried flower petals, such as lavender buds, rehydrating, and sometimes forming mold. So the answer depends on where you live or where the soaps are stored.
Hi lovely green :)
I wanted to ask if the Ultramarine Violet color considered as natural color and from where I can get them please
Hi Haifa, Ultramarine Violet is considered ‘nature-identical’ since it is indistinguishable from the mineral found in nature. However, it’s not mined from the earth but rather re-created in a controlled environment. This is mainly to ensure it’s not contaminated with heavy metals such as arsenic and lead, but because of how it’s produced, it’s not considered natural. I still use it and other nature-identical minerals, though :) They’re also the same pigments that are used in mineral make-up.
Hi there! I’m thinking about adding taro powder or puree (I haven’t decided yet) as a colorant, do you think it would have any bad effects since it has starch?
PS. thank you for the recipe!
Hi Julia, an interesting question! I’ve not used taro in soapmaking before so can’t say what your bars would come out looking like. I suspect that the powder would need to be reconstituted and if you used purple taro, the bars would come out brown though. As for starch — in small amounts (like you’d use with taro) starch can create silky feeling bars and lather.
Sorry I forgot to ask, why do you add the shea butter at trace.
It’s optional to add it at trace, but the idea is to add it to the mix so that it’s not emulsified with the lye. Oils and fats that are emulsified will (most likely) turn into soap first, leaving the fats added after trace to (mostly) survive in the bars as the superfat.
How can I replace the palm oil? It isn’t available in my country 😞
Just make a different soap recipe :) For example, to make this eco-friendly soap recipe a lavender soap, simply add the same amount of lavender essential oil as in this recipe.
how can I prevent the turning of colors though? I purchased clear glycerin and goats milk but I want the pretty colors of the flowers to appear so I can re sell= Is there any way to keep that color?
Because of the pH of soap, lavender buds will turn brown if you mix them into your soap bars. I would not suggest doing this for soap you hope to sell — brown lavender buds look suspiciously like mouse droppings!
How do you determine when to use GSE?
You can use it in every soap recipe or opt not to use it — it’s an optional ingredient that can help prolong the soap’s life. It’s not a preservative but helps free-floating oils from going rancid too quickly. Ideal for superfats that can spoil quickly.
Hi Today its been my second time attempting this recipe and I’ve broken my blender while I was trying to get a thick consistency but in my opinion it was too watery but everything else was absolutely fine. What did I do wrong?
So many things and all simple human error. You could be using the wrong ingredients, mixing at the wrong time, not stick-blending properly, etc. PS — if you’re using an ordinary blender, then there’s where you’re going wrong.
Hi, I’m thinking of making this soap for a student sustainability club at my university. Because of this, I can’t use palm oil nor animal products for ethical reasons. Can I omit the palm oil altogether and replace it with olive oil? If not, what would you suggest? Thanks
You should read this piece: https://lovelygreens.com/avoiding-palm-oil-in-soap-making/
If you have any questions on how to make this natural lavender soap, please ask :)
The Amazon product linked to for the Ultramarine Violet color is currently out of stock. ? I know it is an optional ingredient, but I am trying to find a similar product on Amazon. I see mica powders—are these the same thing?
Thank you!
Micas are a little different and can sometimes act up in cold-process soap. If you want to use another retailer, I’ve listed some places to get soap supplies here.
Hi. I have lavender infused olive oil and would like to make a pure castile pastel red and green soap. Will the infused oil affect the colour of the soap?
Thanks.
Probably not :)
hi can I just double the lavender soap receipe or would I have to adjust the lye /water amounts.
Feel free to double/triple/quadruple… it to your heart’s content. Just remember that larger batches of soap can heat up quicker and retain it for longer. If you pour all of it into a large loaf mould then temperature should be adjusted or you could get a partial gel. Not a big deal but it can affect the colour of your soap