Many years ago, when I first tried to make a soap and water spray for my plants, I used dish soap. It badly burned the leaves on a plant. I then learned that much of what we call "dish soap" is more correctly called "dish detergent."
You need to use real soap to make the mixture. Read the label on whatever you use, to be sure it isn't a detergent.
These days, I use Dr. Bonner's soap.
"Isn't it enough to see that a garden is beautiful without having to believe that there are fairies at the bottom of it too?" - Douglas Adams