Clustered Bellflower
Clustered bellflower (Campanula glomerata) is an upright border bellflower with dense heads of violet‑blue bells. Flower clusters top 12 to 18 inch stems in late spring to early summer. Plants form clumps and may spread by short rhizomes. It is hardy and adaptable in sun to light shade with regular moisture. Stems make good cuts when half the cluster is open. Fragrance is minimal.
At‑a‑glance
- Group/Class: Perennial species; clump‑forming
- Height × spread: 12-18 in × 6-12 in (30-45 cm × 15-30 cm)
- Bloom window: May to July
- Color & flower form: Violet to lavender‑blue; dense terminal clusters; single
- Fragrance: 0 none
- USDA hardiness: zones 3-8
- Breeder / Year / Origin: unknown
- Cut‑flower notes: Good cut per botanic‑garden notes; typical vase life unknown
- Pet safety: safe
How it differs
- Densely clustered heads rather than solitary bells
- More upright and robust than many low, creeping species
- Cold‑hardy and dependable in northern gardens
- Can spread by rhizomes more than many clumpers
Strengths
- Showy early‑summer display
- Good for cutting and pollinators
- Deer browsing is uncommon
- Hardy across cold climates
Care in one minute
- Light: full sun in cool climates; light afternoon shade where summers are hot
- Soil: average, well‑drained; avoid waterlogged sites
- Water: regular moisture through spring bloom
- Groom: deadhead spent stems to focus energy into the clump
- Divide clumps every 3 to 5 years to control spread
Watch‑outs
- Can be vigorous and spread beyond its clump
- Needs division every few years to maintain vigor
- Flowering may shorten in sustained heat
Best uses (tags)
borders, cutting, naturalizing, pollinators
Provenance note
Native to Europe and temperate Asia; widely cultivated and sometimes naturalized in North America.
References
- Missouri Botanical Garden Plant Finder: Campanula glomerata
- RHS: Campanula glomerata
- Native Plant Trust Go Botany: Campanula glomerata
Written by: Your Flowers Guide editorial team
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