Where should one add iOS dependencies in a plugin?

I'm trying to add a dependency to my Flutter plugin for iOS and I'm wondering where this should be added.
Should I let the user add this to his Podfile or should I add the dependency to my plugin (which would make it easier for the user) myself. And if I should add it to my plugin myself, where should I add it? The example project has a Podfile, but the actual root plugin project doesn't. Should I just create one myself in the iOS folder of my plugin? And if so, how? I can't use pod init because the plugin's iOS directory does not actually contain an Xcode project.