Question: Do I need to use a preservative when I water down castile soap?

Have you ever wondered if you need to use a preservative when you water down castile soap?  Megan asked that very question.  I do not know the answer to that question but  Susan Barkley-Nichols of Point of Interest answered that very question in a post called Do I need to use a preservative when I water down castile soap?  This posting should give the exact answer.