Agapanthus campanulatus (white)

Well, it's the most hardy of all the Agapanthus. I assume that the pot is large enough to accommodate all three plants and their roots? Is it in the most sunny place you have? The only doubt that I have about planting Agapanthus with other plants is that its roots are fleshy and spread out quite a way, and it prefers to be pot-bound. So if you lost one of the other two, you would have problems replacing it without damaging the Agapanthus roots. Good luck.