Ants

I recently bought a "Carmine Bells" plant (I'm sorry, I can't remember the botanical name) and put it in a glazed pot on the top rail of a 5 foot privacy fence to make sure it got enough sun. Over the weekend I realized that a long thread of ants was climbing up and down the side of the pot. I have check thoroughly for aphids or anything else that might attract the ants and can't find anything.

Will they hurt they plant? Should I try to get rid of them? Or are they beneficial in some way?

Thanks!

In my experience, sometimes ants can be harmful to the roots of the plant...I would try to discourage them..by applying citrus oil... would that work?

Thanks!