These plants are encroaching on the walk way! I've never seen these in a planting like this. On the occasions when I've seen them growing, it was always just a large clump. This makes for a spectacular walkway. Not what I usually think of concerning a border planting. Just a single plant without companions.

It's very much a 'done thing' over here to soften up hard edges of things like paths with plants. You can see from this wider shot that a lot of the plants in this border are allowed to expand over the stonework. To be fair this is a path in front of the hall that isn't used very much as there is another main path to the left of here.

I think plants just do that naturally. Mine do anyway. That planting looks really good here. Both photos.