'Superba'
Clustered Bellflower
"Here stood a shattered archway plumed with fern;
And here had fallen a great part of a tower,
Whole, like a crag that tumbles from the cliff,
And like a crag was gay with wilding flower."
-Alfred Lord Tennyson
Campanula glomerata dahurica 'Superba' has purple flowers with a glistening almost metalic sheen. It wants full sun in moist fertile soil. It is definitely not one of the drought-hardy campanulas & should be placed in a regularly watered location.
It makes few other demands in order to be an extremely long-lived perennial. It forms a thick low-growing clump of leaves that send up twenty-inch stems with clusters of the deepest purple flowers. The spreading clump should be dug up for division every third or fourth year.
The stalks of flowers are at their height of beauty in early summer. When they are spent, deadheading & trimming the leaves will usually induce a second flush of flowers. If it loves its location it may self-seed with abandon, to the point where some people regard it as a bit too aggressive. Deadheading before it seeds will solve that potential problem. It isn't apt to entirely escape the garden since it will not spread into dry areas.
We started our clump from a single two-inch seedling from Heronswood, planted not far from another sun & moisture-loving perennial, Prairie Mallow & visible in the above photo 'Kentish Hero' Slipperwort. The teency 'Superba' seedling did nothing much its first year & a half. I'd just about forgotten it was even in the perennial bed until its buds & blooms appeared one June.
C. carpatica var turbinata 'Pearl Deep Blue'