Things You'll Need
Chef's knife or hatchet
Sage, thyme, rosemary, lavender, or lemon verbana
Distilled or filtered water
Container (pump bottle, empty shampoo bottle, or glass jar)
Spoon or electric mixer
Yucca, also known as soaptree, is an edible plant with tuberous roots which are rife with natural saponins, the soap-making (or saponifying) ingredient which causes lather as well as the carbonated soda ingredient that causes root beer or sarsaparilla to froth. The root also has emollient properties which have a soothing and moisturizing effect, making yucca root soap ideal for people with sensitive skin, or who have allergies to chemical lye or glycerin soaps. In addition, yucca soap bars can be used interchangeably as human and pet shampoo.
Processing Yucca Root
Clean the yucca root thoroughly with a vegetable brush to remove loose dirt and loosen the skin.
Peel the outer layer of skin off with a vegetable peeler. Take care to ensure the inner, white roots remain free of dirt from the outer peel.
Chop the root into small pieces about the size of golf balls for processing. Yucca roots are compact and sticky to work with, so a sharp chef's knife or hatchet will be best for this job.
Pulverize smaller bits of yucca root in a blender.
Spread evenly onto a wax-paper-lined cookie sheet and set it in the oven to dry at about 200 degrees Fahrenheit for an hour or more. Check the pulp frequently as drying time will vary.
Yucca Liquid Soap
Chop an herb with a strong and pleasant scent (such as sage, thyme, rosemary, lavender, or lemon verbana) and place in a glass jar filled with 100 mm of distilled or filtered spring water. Place the jar in the hot sun for 4 to 6 hours to infuse the water with the herb.
Grate a block of dried yucca root finely into a dish until you have about 100 grams of yucca powder.
Add yucca root powder to 400 mm of distilled water in a pot and bring to a boil for ten minutes. Reduce to a simmer until the root has dissolved. Stir constantly. The root will lather, so watch the mixture carefully to prevent boil-over.
Add yucca liquid to your herbal infusion. Add 15 to 20 drops of essential oil which has a scent you find compatible with the scent of your herbal infusion. Mix in 2 tbsp. vegetable glycerin and stir. Place the mixture in a pump bottle, a reused shampoo bottle, or a glass jar for storage.
Yucca Bar Soap
Process yucca root into a pulp using the instructions above. Set the pulp aside before drying.
Remove yucca pulp to a bowl and add 15 to 20 drops of your favorite essential oil. Stir mixture together until essential oil is worked in. The pulp will be thick and sticky, so use a strong-handled spoon or an electric mixer.
Line a cake pan with wax paper and spread the yucca root pulp and essential oil mixture onto the paper. Use a narrow pan to create thick bars of soap.
Set the pan in the sun to dry or bake in the oven at about 200 degrees for an hour or so until dry to the touch.
Cut the dried yucca into bars of soap using a kitchen knife, and your soap is ready to use.
For extra-emollient bar soap, try adding crushed almond powder or rolled oats to your yucca bar to both soften and exfoliate your skin.
Test your yucca concoction on a small patch of skin to ensure you don't have allergies and/or consult a doctor before using.