How to use castile soap

Washing hands with liquid castile soap

Castile soap is a versatile, eco-friendly ingredient used in many DIY personal care and household cleaning recipes. (Photo: Burst via Pexels)

What’s castile soap?

Castile soap is versatile and gentle on people and the environment.

It’s named for Castile, Spain, a region renowned for its olive oil. Authentic castile soap is made of plant oils — coconut, hemp, sunflower seed, jojoba and olive. (Avoid brands that use palm oil. That’s devastating biodiverse forests where many endangered species live.) Oils are mixed with an alkali — sodium hydroxide for solid soap and potassium hydroxide for liquid.

What makes castile soap eco-friendly?

  • It’s biodegradable.
  • It’s vegan.
  • It’s not tested on animals (check for Leaping Bunny certification).
  • It’s scent-free (no synthetic fragrances, even natural essential oils).
  • You can refill containers at zero waste and organic grocers or health food stores.
  • You can support a local brand.
  • It’s free of artificial foaming agents, harsh cleansers, deconstructed fatty acids from vegetable oils or fats (a.k.a. oleochemicals), petrochemicals and/or chemical antibacterial agents (such as triclosan).
  • It’s concentrated, so a little goes a long way.

Note: Read labels carefully and choose products with vegetable-based ingredients. “Liquid soap” doesn’t mean “plant-based.”

Empty jars and wooden spoon

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Thirteen ways to use liquid castile soap

  1. Make hand or body wash.
  2. Wash fruits and veggies. Add a squirt to a sinkful of water. Rinse.
  3. Make all-purpose spray and all-purpose scour.
  4. Make liquid laundry soap (not a detergent).
  5. Make diaper wipe solution. (Add a few drops to a squirt bottle of water.)
  6. Make DIY pest repellant.
  7. Wash reusable menstrual cups.
  8. Clean (some of) your sex toys.
  9. Clean makeup brushes.
  10. Wash floors. (Add a squirt to a bucketful of water.)
  11. Use in a carpet washing machine.
  12. Wash the car. (Add a squirt to a bucket of water.)
  13. Wash the dog.