Calendula Buttermilk Lavender Soap


I made 4 different kinds of soap to give away as presents last year. The first type of soap I made was a Calendula Buttermilk Lavender Bar.


I created all my own recipes for the soaps. I used for all of my calculations. Here is a link to their Soapcalc Lye Calculator.  You enter in the type of oils you want to use and the size of the recipe and it will tell you exactly how much lye, water, and oils you need in pounds, ounces, and grams. So convenient! It also tells you how the bar will turn out in terms of conditioning, lather, hardness, etc… So you can play around with oil ratios until you get the qualities you are looking for in the finished bar.

I wanted something really nourishing and soothing to the skin so I used a higher percentage of olive oil than usual. Also, I wanted this bar of soap to be more conditioning so I set my superfat at 7% in Soapcalc. For more details about the overall process of making soap you can read through my post Lavender Rosemary Soap.


Once the recipe was created, my first step was to measure out the oils. I wanted to infuse the oils with dried calendula blossoms so I measured my oils into a glass baking dish instead of a pot.


Calendula is an herb known for its skin soothing properties. It is anti-bacterial, anti-viral, anti-fungal, anti-inflammatory and helps to regenerate skin cells. Yeah, this herb is amazing for the skin!


I decided to use 1 oz of dried herb to 1 pound of oils. I had 2 pounds of oils in my soap recipe, so I weighed out 2 oz of calendula blossoms.


I have a coffee grinder dedicated to grinding my herbs. I could have infused the whole blossoms into the oil, but grinding them increases the surface area exposed, getting the most ‘goodies’ from the herbs.



I had the oils melting in the oven while I was grinding the calendula. Then once the oils were melted, I stirred in the calendula and placed it in the oven to infuse.


It is best to keep the oven between 150-200 degrees F for herbal infused oils. Otherwise you start cooking the herb, which you don’t want. An oven thermometer is really helpful to know if you are in those temperature ranges. My big oven can be up to 75 degrees off sometimes! As a rule of thumb, if your oil starts bubbling the temperature is too high and needs to be turned down.


The oil infused for 2 and half hours in the oven.


Then it was ready to strain. I put my soap mixing pot on the scale, tared the scale, and set up my strainer (a flour sack towel). Using the scale was crucial so I knew how much oil I got out after straining.


Then I poured everything into the towel, gathered up the edges, and started squeezing.


I am glad I was measuring, because I lost 3 oz. of oil that I couldn’t squeeze out of the calendula. So I had to add extra oil to make it equal the 32 oz I needed for the recipe. In the future I will add extra in the beginning before I infuse to compensate for any oil that is lost during the infusing process.


I also wanted to add buttermilk to the recipe to make it even more conditioning and nourishing. There are a couple of ways to add milk to a soap recipe. The main problem is that when lye and liquid are mixed together it gets really hot. If milk is added straight to lye it can cause the milk to burn and curdle. Not good. Another option is to make a concentrated lye mixture with water and then add the milk to the oils separately. I decided to go for the second option.

Let me give you some numbers so it makes more sense. I needed 4.5 oz of lye and 12.66 oz of liquid for my lye mixture. I used equal parts lye and water to make my concentrate. So, 4.5 oz of lye and 4.5 oz of water. The remainder of the liquid needed for the recipe was (12.66-4.5)=8.16 oz of buttermilk.  So, once my oils were ready, I added the concentrated lye mixture and then the buttermilk. This worked out really well for me and kept the milk from burning.


Then the rest was easy. I used my immersion blender until it started to thicken. Then I added in the lavender essential oil and blended more until it formed small peaks when I lifted up the blender.


Then I spread it out in a pan lined with parchment paper (wax paper doesn’t work). Word to the wise, don’t use an aluminum pan as a soap mold. Even though I lined it with parchment paper, the lye ate through some of the lining on the pan. I learned my lesson, and will only use glass, wood or silicone molds from now on.


24 hours later, once the soap had set up, I cut it into bars and let it cure for 4 weeks. I made all my Christmas soaps the week of Thanksgiving break so it would be ready by Christmas.


Chris wrapped each bar with a strip of construction paper while I was at work one day. Thanks babe! Then I made labels and glued them on to make the finished product. I love how they turned out!


 Calendula Buttermilk Lavender Bar

30% Coconut Oil

40% Olive Oil

25% Tallow

5%  Castor Oil

1 oz of dried calendula blossoms per pound of oils

7% superfat




25 grams of lavender essential oil

Calculate your recipe using Soapcalc to get your precise amounts of fats, lye and water based on the amount of oils you want to use. For this recipe I used 32 oz of oils.

Measure out oils into an oven safe container, let them melt and mix in ground up calendula blossoms. Let infuse in an oven at 150-200 degrees F for 2-2.5 hours. Strain out the calendula.

Make a concentrated lye mixture using equal parts lye and water. Measure out the remainder of the liquid required in the recipe as buttermilk. Once the oil, buttermilk and lye mixture are cooled to about the same temperature mix together and blend with an immersion blender. Add in the lavender essential oil and blend more until the soap starts to thicken and forms soft peaks. Then pour into mold.

Let saponify for 24 hours, then unmold and slice into bars. Let cure for 4-6 weeks.

Don't be shy, leave a comment and let me know what you think!

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