Agapanthus dilemma

diggingdoris

I was given a pot of fabulous agapanthus this year and I had 3 great flower stems on it. I am not sure whether to cut the stems back now they've finished flowering or to leave them to die back like I do with the lilies. On searching the internet there seems to be conflicting advice, so I thought I'd ask my fellow gardeners on here. I'd quite like to save one head to collect seeds, presumably I leave it on the plant to mature them.

Dovefromabove

I remove the old flowers before they can form seeds and leave the stems and leaves to die back naturally - of course not all types die back in the winter.  

Yes, to obtain viable seeds the seedhead needs to ripen on the plant.