Natural soap making is a creative and rewarding process—but when you incorporate powdered Mimosa Hostilis Root Bark (MHRB), it becomes an art form. Known for its beautiful purple-brown hues, powdered MHRB adds natural color, subtle texture, and an earthy appeal to handcrafted soaps.
In this tutorial, you’ll learn how to make soap using powdered MHRB, why it’s such a sought-after ingredient, and how to work with it safely and effectively in cold process soap.
Whether you’re a beginner looking to make your first batch or an experienced soap maker curious about botanical dyes, this guide gives you everything you need to create stunning soap bars naturally colored with Mimosa Hostilis.
What Is Powdered MHRB?
Mimosa Hostilis Root Bark (MHRB) is the dried and ground root bark of the Mimosa tenuiflora tree, native to Mexico and Brazil. Traditionally used for its regenerative properties in skin care and known for its rich dye potential, powdered MHRB brings a range of purples, browns, and even pinkish hues to soaps depending on the pH and other ingredients.
It is valued in artisan soap circles for:
- Its natural antioxidant and tannin content
- A unique, earthy purple-brown hue
- A rustic speckled texture when unfiltered
- Its compatibility with other botanicals
MHRB is often used in natural dye projects, and in soap, it doubles as a skin-friendly additive and a natural colorant.
Tools & Supplies You’ll Need
Ingredients:
- 16 oz (454g) olive oil
- 8 oz (227g) coconut oil
- 8 oz (227g) shea butter or mango butter
- 3 oz (85g) castor oil
- 9 oz (255g) distilled water
- 3.9 oz (110g) lye (sodium hydroxide)
- 1–2 tsp powdered MHRB
- Optional: essential oils (lavender, cedarwood, rosemary work well)
- Optional: kaolin clay or colloidal oatmeal for added texture
Equipment:
- Digital scale
- Safety goggles and gloves
- Stainless steel or plastic mixing bowls
- Silicone spatula
- Immersion blender
- Soap mold
- Thermometer
- Vinegar for clean-up (neutralizes lye)
Step-by-Step: How to Make Soap with Powdered MHRB
Step 1: Safety First
Before working with lye, put on gloves and goggles. Work in a well-ventilated area and always add lye to water (never the other way around) to avoid dangerous splashes or fumes.
Step 2: Measure and Mix the Lye Solution
- Carefully weigh 3.9 oz (110g) of lye and 9 oz (255g) of distilled water.
- Slowly add the lye to the water while stirring gently.
- Allow the solution to cool to about 100–110°F (38–43°C).
Step 3: Melt the Oils
- In a large bowl or pot, combine olive oil, coconut oil, shea butter, and castor oil.
- Melt gently over low heat or in a microwave until fully liquified.
- Let cool to around 100–110°F to match the lye solution.
Step 4: Add the Powdered MHRB
- While the oils are cooling, mix 1–2 teaspoons of powdered MHRB with a small amount of warm oil or water to create a paste.
- This helps avoid clumps and ensures even dispersion in your soap batter.
- Stir the MHRB paste into the melted oils thoroughly.
Note: The natural dye tones of MHRB vary depending on how long the soap cures, the base oils used, and your pH. Expect a range from light lavender to earthy purple-brown.
Step 5: Combine Oils and Lye
- Slowly pour the lye solution into the oils.
- Use a stick blender to mix until you reach light trace (when the batter thickens like thin pudding).
Step 6: Add Essential Oils (Optional)
- Once at trace, add any essential oils or additional botanicals.
- Blend lightly to incorporate.
Step 7: Pour into Mold
- Pour your soap batter into a silicone mold.
- Tap gently to release air bubbles.
Step 8: Insulate and Cure
- Cover with a lid or cardboard and insulate with a towel.
- Allow to sit for 24–48 hours.
- Unmold and cut into bars.
- Cure for 4–6 weeks in a cool, dry area to fully harden and mellow the color.
Color Results: What to Expect
Powdered MHRB in soap can surprise you! The final shade depends on several factors:
- pH of your soap (higher pH may darken the color)
- How much MHRB is used
- Type of oils and additives
Expect shades of:
- Soft lavender
- Mauve-gray
- Rich reddish-brown
- Earthy purple
For a lighter tone, use ½ tsp. For bold color, go with 1½–2 tsp and experiment.
Tips for Best Results
- Test small batches before committing to a large pour.
- Pair with white kaolin clay to help lighter tones stand out.
- Use stainless steel tools—MHRB may stain porous materials.
- Document your batch: date, temp, oil combo, and MHRB amount for future reference.
Is MHRB Safe in Soap?
Yes! Powdered Mimosa Hostilis is safe for soapmaking when sourced from a reputable supplier and used properly. It’s used topically in many traditional medicines and modern skincare products.
Avoid using if you are allergic to legumes or tannin-rich plants. Always test a bar before full use, especially for facial soap.
Why Use MHRB in Soap?
Powdered MHRB is unique among natural dye ingredients. Here’s why artisans love it:
- Offers naturally occurring anthocyanins and tannins
- Creates a rustic botanical look
- Pairs well with essential oils
- Feels luxurious without synthetic dyes
- Adds depth to your branding as a maker using rare and ethically sourced botanicals
Where to Buy High-Quality Powdered MHRB
You can find premium, ethically sourced MHRB powder at Tenuiflora Shop. Our root bark is finely milled, organically handled, and trusted by artisans across the U.S. and Canada.
We also offer MHRB in other textures (shredded, chipped) for dye and extraction projects.
Final Thoughts
Making soap with powdered MHRB isn’t just about color—it’s about creating something beautiful, natural, and personal. Whether you love its heritage in natural medicine, its earthy color palette, or just the feel of something handmade, MHRB is a worthy addition to your botanical toolkit.
As you experiment with natural dye ingredients in your soap, keep a curious heart and a detailed log. Every batch teaches something new.
So go ahead—make, mix, and marvel. And if you’re ready to explore more natural dye possibilities, visit SkillShare for extended resources on plant-based pigment use.
Tagged: powdered MHRB, MHRB soap, natural dye, soap making tutorial, botanical color, herbal soap, handmade soap, mimosa hostilis root bark