This grower is fairly sure of this plant identification.
I think they are Delft, or very similar. I need to divide them soon.
Agapanthus ‘Delft Blue’ (African lily). Produces a round, mid-blue head of funnel-shaped flowers in late summer. Each trumpet bloom has a central stripe of blue-purple. The leaves are mid green.
Suitable for coastal conditions.
Borders, containers, gravel gardens.