Campanula glomerata var. acaulis hort.
Clustered Bellflower. A vigorous, variable, rhizomatous, clump-forming perennial which has ovate to lance-shaped, round-toothed, dark green leaves. From June to August, dense, terminal racemes of deep purple, bell-shaped flowers are borne.
Grow in moist but well-drained, fertile, neutral to alkaline soil in sun or partial shade. It will reach a height of 20cm and a spread of 60cm.