Superba Bellflower
Bold Violet Flower Clusters for the Summer Border
Superba Bellflower (Campanula glomerata 'Superba') makes a strong statement with dense, upward-facing clusters of deep violet-purple bells crowded atop upright stems in early to midsummer. A vigorous, easygoing perennial, it draws bees and butterflies and spreads to form a bold patch of color. Deer-resistant and reliably hardy, it's a striking cottage-garden plant for sunny and part-shade borders in Edina, Woodbury, and Maple Grove.
Superba Bellflower Plant Details
| Attribute | Detail |
|---|---|
| Botanical Name | Campanula glomerata 'Superba' |
| Mature Size | 18–24 in. tall, 18–24 in. wide |
| Hardiness Zone | 3–8 (Twin Cities is zone 4b–5a — fully hardy) |
| Light | Full sun to part shade |
| Bloom Time | Early to midsummer, with rebloom if cut back |
| Flower Color | Deep violet-purple |
| Soil | Adaptable — tolerates clay-loam and average drainage |
| Winter Hardiness | Reliable to -30°F once established |
| Deer Resistance | Rarely browsed by deer or rabbits |
Landscape Uses in Minnesota
Bold border color: Its clustered violet blooms make a vivid mid-border patch. Space 18–24 inches apart.
Pollinator and cottage gardens: Bees and butterflies love the flowers, and the spreading habit fills space. Pair with Shasta daisy, yarrow, and catmint.
Best Time to Plant in Minnesota
Plant in spring (late April–May) or early fall. Water through establishment.
How to Plant Superba Bellflower
Dig a hole twice the pot's width at the same depth, loosening clay and mixing in compost. Set the crown level, backfill, water in, and mulch 2 inches deep. Space 18–24 inches apart.
Watering Superba Bellflower
First year: Water every 2–3 days at first, then weekly. Stop 2–3 weeks before the ground freezes.
After year one: Water during dry spells. Cut back spent flower stems to encourage rebloom and keep it tidy.
Q: Will it survive a Minnesota winter?
Easily — hardy to zone 3, returning each spring.
Q: Does it spread?
Yes — clustered bellflower spreads to form a patch. Divide every few years and edge it to keep it in bounds.
Q: Is it deer-resistant?
Yes — deer and rabbits rarely bother it.
Q: How do I get rebloom?
Cut back the spent flower stems after the first flush to encourage more bloom.
You May Also Like
Rapido Blue Bellflower (Campanula carpatica): A compact blue bellflower for the front of the border.
Shasta Daisy (Leucanthemum): A white-daisy partner for cottage borders.
Catmint (Nepeta): A deer-resistant blue-flowered companion.