September 30, 2005 How was I supposed to know you can't put dishsoap in the dishwasher?? September 30, 2005/ Charlie O'Donnell Photo 661, originally uploaded by ceonyc. I ran out of Cascade this morning, and so I used dishsoap.I've never had a dishwasher before.My parents never had a dishwasher when I was growing up. How was I supposed to know the outcome?Well, let me tell you, my floor is really clean now. :/And that "Cancel/Drain" button? Pure genius.