by Sara Williams
Campanula is the Latin word for “little bell” and describes the flowers of this genus – formed from the 5 lobes that are fused at the base in a bell-like form. The flowers are most commonly blue but can be white or in some species, shades of pink.
Most bellflowers thrive in moist, well drained soils in sun or partial shade. Mulch is beneficial to keep the soil cool and moist and to control weed germination.
Medium-sized species such as C. persicifolia and C. glomerata are striking in drifts in the mid-border. Low growing species such as C. cochlearifolia and C. carpatica are excellent plants at the edge of the border or in rock gardens.
Carpathian bellflower (Campanula carpatica) forms a 15- to 20-cm (6-8-in.) tussock of leaves with relatively large blue or white upturned flowers on stems up to 30 cm (12 in.) high from spring to late summer. Divide it every two to three years to maintain vigor. The following varieties are less hardy but more available than the species.
‘Blue Clips’ is more compact with blue flowers.
‘Deep Blue Clips’ is a compact dark blue form.
‘White Clips’ is a compact white flowered form.
Dwarf bellflower (or fairy thimble bellflower) (C. cochlearifolia) is a very compact species, 10 to 15 cm (4-6 in.) in height with tiny, deep green leaves and nodding blue or white flowers. Native to the mountains of Europe, the species name is from the Latin word for “little spoon” and describes the shape of the leaves. The plants spread by rhizomes to fill available spaces in the rock garden, around paving stones or at the edge of a path or border. It does best in well-drained soil in full sun.
‘Alba’ is a white form that is less winter hardy than the species.
‘Bavaria Blue’ has light blue flowers.
‘Blue Baby’ is dark blue.
‘Elizabeth Oliver’ has tiny double blue flowers.
‘Miranda’ has icy pale blue flowers.
Clustered bellflower (C. glomerata) is native to Europe and northern Asia with flowers clustered at the top of the stem. Plants are 15 to 60 cm (6-24 in.) high with a spread of 30 to 100 cm (12-36 in.). Shear after bloom for a tidier appearance. Plant them in full sun in well drained soils.
‘Acaulis’ is a shorter form that is almost stemless.
var. alba has white flowers and is 45 to 60 cm (18-24 in.) in height.
‘Superba’ is a vigorous, slightly taller variety with deep violet blue flowers.
Peach-leaved bellflower (C. persicifolia), native to the Balkan peninsula from Turkey into Russia, has foliage similar to a peach as suggested by both the common and Latin names. It is adapted to sun or partial shade in average well-drained soil. The plants spread by rhizomes, forming rosettes of deep green leaves with flower stems to 80 to 100 cm (30-40 in.) with blue or white flowers. It is easy to grow from seed.
‘Alba’ is a white flowered form, up to 80 cm (30 in.) tall.
‘Chettle Charm’ has elegant white flowers edged with blue. It is 75 to 90 cm (30-35 in.) high.
‘Takion Blue’ is a compact form, 40 to 50 cm (15-20 in.) high with pale blue flowers.
‘Takion White’ is a compact white flowered selection of 40 to 50 cm (15-20 in.) in height.
BEWARE the creeping bellflower (C. rapunculoides). This one is considered a serious weed of gardens, back alleys and even lawns. Several blooming, slender stems (in clumps or spread out) may reach 1 metre (3 feet) high or more. Nodding, deep blue to lavender bells develop singly from leaf axils on one side of the upper stem. They may seem harmless and even make a nice cut flower. But once in your yard or neighbourhood, they are poorly behaved, spreading rampantly, and take a great deal of effort to eradicate.
Sara Williams is the author of Gardening Naturally with Hugh Skinner, Creating the Prairie Xeriscape, and with Bob Bors, Growing Fruit in Northern Gardens. She gives workshops on a wide range of gardening topics throughout the prairies.
This column is provided courtesy of the Saskatchewan Perennial Society (SPS; firstname.lastname@example.org). Check our website saskperennial.ca) or Facebook page (facebook.com/saskperennial). All Saskatchewan Perennial Society events are on hold until further notice.