Content Detail

Clustered purple flowers form on upright, hairy stems in summer, lasting two to three weeks. The plant forms open clumps by spreading underground rhizomes. Best used in informal areas as it can be an aggressive spreader.

  • Family (English) Bellflower
  • Family (botanic) Campanulaceae
  • Tree or plant type Perennial
  • Native locale Non-native
  • Size range Medium plant (12-24 inches), Large plant (more than 24 inches)
  • Light exposure Full sun (6 hrs direct light daily), Partial sun / shade (4-6 hrs light daily)
  • Hardiness zones Zone 3, Zone 4, Zone 5 (Northern Illinois), Zone 6 (City of Chicago), Zone 7, Zone 8
  • Soil preference Moist, well-drained soil
  • Tolerances Road salt
  • Season of interest late spring, early summer, midsummer
  • Flower color and fragrance Blue, Purple
  • Shape or form Upright
  • Growth rate Fast


Clustered bellflower grows 18 to 24 inches tall and about 18 inches wide. Plant will grow wider over time as it spreads by rhizomes.

Native geographic location and habitat:

Native to Europe. 

Attracts birds or pollinators:

Butterflies, hummingbirds, and other pollinators are attracted to the flowers.

Leaf description:

Narrow, heart-shaped, alternate leaves at the bottom of the stems have petioles (leaf stems). The leaves vary in size and are hairy both on the top and on the bottom surfaces.

Flower description:

As many as 15 star-shaped flowers clump together at the top of the stem or where the leaves attach to the stem. Flowers are medium blue to purple and face upward.

Fruit description:

Fruit is a small capsule.

Plant care:

Plant in full or part sun and moist soil. In hot climates, prefers moist soil and part sun. The plants should be divided in spring or fall. Do not prune in the fall, but leave the plant up until spring clean-up. Deadhead plants to prolong the bloom time. Can be somewhat short-lived.

List of pests, diseases, tolerances and resistance:

No serious problems, although the plant is attractive to slugs and snails. Salt tolerant. Deer and rabbit resistant

Freya clustered bellflower (Campanula glomerata ‘Freya’):

A variety that sports a large number of lilac-blue flowers from May until July on somewhat shorter stems.

Superba clustered bellflower (Campanula glomerata ‘Superba’):

A more heat-tolerant cultivar with purple flowers. 


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