The Hot Pepper

Cocoa shells. You can get them at some nuseries. Worked for me. Cats seem to hate it.

I have heard about that, but we have several friendly local dogs that aren't an issue that I don't want to risk harming. Our feral cats are the problem. I have heard that capsaicin makes a good deterrent as well. I wonder if I made a spray with orange/lemon oil and superhot peppers if that would be a safer alternative.