It’s possible to grow your own soap source through a fantastic herbal plant called Soapwort. Soapwort is one of those little blessings in nature. It is drought tolerant, an easy keeper and yes, it can even be used to make soap.
Soapwort can produce a nice liquid soap suitable for washing delicate fabrics and can even be a shampoo.
Here is a link worth saving for your own DIY soap making needs: http://theherbgardener.blogspot.mx/2010/03/how-to-make-organic-soap-using-soapwort.html
And here is one of many sources available to get your Soapwort seeds: https://www.seedman.com/soapwort.htm