Does peppermint oil repel rats?

Answer 1

I used it for mice and it did nothing.Just like those fancy ultrasonic devices.

Answer 2

We use McCormick Spearmint flavoring in combine an truck cabs during the off season.  It helps a lot.

Answer 3

Only a tiny bit.  About as much as it repels humans.  

Balsam fir repels rats.  There is even a company called Fresh Cab that sells balsam fir for this purpose.  It smells great to humans, but rodents hate it.