Thanks for your answers and suggestions. I definitely need to raise the soil level in the pot. The ficus are newly transplanted into their pots so I wanted to wait a little for the root structure to settle before disturbing. Also, in regards to the light requirement for the mint, it is hard to tell because that picture was taken at night but the ficus sit in front of gigantic arched windows that let in tons of natural light. I'm not worried about the pennyroyal growing, I just don't want its roots to suffocate the ficus. I think I will try it in one of the three first and see how it goes. I will post pictures soon.
Thanks!
