(I'm new at this, so I don't know if this is too late to respond.) In Wikipedia, the blossoms shown are much finer than this image.
This photo resembles a plant I detested in my old garden, which had been a nursery in the 20's, 30's and 40's. The Campanula that grew so invasively there, was either Campanula trachelium or Campanula latifolia macrantha, I believe. It had a thicker white root than Campanula rapunculoides, larger basal leaves, spear shaped, and flowered haphazardly, up and down the stalk over a two month period. It did not look nice in bouquets, because the wimpy, dishrag blue spent blossoms, would be all over, detracting from the lovely fresh blue blossoms, and new blossoms did not open well on a cut stalk. It set seed rather quickly, and the upper stalk and the seed pods were prickly, so dead heading was unpleasant and finicky. They always seemed to be spilling seed out when disturbed. And yet, in August, when fewer perennials were blooming, their blue / mauve was enticing, so I hated to cut them down too soon.
In going through the Campanulas in ATP, I noticed that the first photo shown for Campanula collina, might instead be Campanula trachelium or Campanula latifolia macrantha. In reviewing images on Google, I feel that Campanula latifolia var. latifolia is quite a bit nicer than the plants I was coping with.
