Campanula is a low growing genus of perennial, herbaceous plants with bell-shaped flowers. Within the genus, there are 300 or more varieties with flower colour ranging from white, red, purple, and blue most common. Campanula species originate in the cool northern regions of the world. The bell-shaped flowers have earned this plant the common name Bellflower. Campanula blue varieties enjoy a cool, damp climate. In the garden, Campanula blue flowers add vibrant colour to the landscape.
Campanula 'Kent Belle'
Kent Belle is a Campanula variety with large, 2 inch long, violet-blue, bell-shaped flowers that hang down towards the ground. The plant grows 18 to 28 inches tall and spreads from a rhizome-like root system. Kent Belle enjoys a cool environment where evening temperatures regularly drop below 21.1 degrees C. In cool climates, a position in full sun is best. In warm climates, an area that gets afternoon shade is preferred. Kent Belle requires consistently damp soil to flourish. This variety is a hybrid that has sterile seeds. Propagation by root division is performed in the spring.
Campanula 'Blaue Clips'
The variety Blaue Clips has violet-blue bell-shaped flowers that face up, giving the impression of a sea of blue when planted in mass. This variety grows 10 inches tall and individual plants have a spread of 15 to 17 inches. The flowers bloom in early, mid and late summer. In cool climates, a position in full sun and rocky, well-draining soil is preferred. This variety is used in rockeries to add a splash of vibrant colour.
Campanula 'Chewton Joy'
The china-blue flowers of the Chewton Joy variety fade to white in the centre of the bell shape. The small flowers face up, showing the delicate contrast between the pale-blue flowers and the white interior. This variety grows 10 inches tall with individual plants spreading 20 inches wide. A hardy variety of Campanula, Chewton Joy is used along the outer border of pathways and flower gardens. A position in full sun with light, alkaline soil is preferred.
Campanula 'Willow Bell'
Willow Bell is a tall variety of Campanula standing 18 to 36 inches. The deep-blue flowers cluster along 24- to 36-inch stems. This heat-sensitive variety requires afternoon shade in warm climates. Willow Bell is self-fertile and will self-propagate from seed. Damp soil and sun to partial shade is ideal. Removing flowers as they fade encourages continuous blooms and prevent self-seeding.
Campanula 'Summertime Blues'
Summertime Blues have silver-blue flowers that droop towards the ground from the tips of 18- to 24-inch stems. The burgundy stems rise above the dark-green leaves. Summertime Blues is a clumping, hybrid form of Campanula blue that does not spread from the rhizome. The seeds are sterile, making this variety easy to control in the garden or landscape. This plant enjoys full sun or partial shade and well-draining, loamy soil.