Hardy to -34°C (-30°F), it is semi-evergreen to evergreen in warm winter climates. They are sun lovers and are easily grown in ordinary free draining soil. Deadheading will promote additional flowering.
Also known as bellflowers they work well in the front of the border, and are at home in the rock garden. They can be used as a groundcover in the mixed perennial border, are useful as a path edging and excellent in containers, hanging baskets and window boxes. The flowers are attractive to bees and can be used as cut flowers.
Sowing:
Sow indoors in autumn to mid spring (Sept-March for flowering in April-August.)
Or sow in late spring (March to April) for flowering in July-August.
The species can also be grown from seed directly sown outdoors in autumn or after the last frost.
The seeds should be sown on the surface of the compost, press lightly into the compost but do not cover as they need light to germinate. The compost should be kept moist at all times.
Cover the seed container with a piece of glass or clear plastic and leave in a temperature of around 16-18°C (60-65°F) in a position which receives diffused light.
Germination between 14 and 28 days. Once some of the seeds have germinated air should be admitted gradually otherwise the seedlings may damp off.
When seedlings have their first pair of true leaves and are large enough to handle, transplant into 7.5cm (3in) pots to grow on in a coldframe. When large enough, plant out into their final position plant out 30-38cm (12-15in) apart. Avoid planting out seedlings until all threat of frost has passed.
Cultivation:
Campanulas are easily grown in average, medium wet, well-drained soil in full sun to part shade. They require an average amount of water, as they do not tolerate really wet or overly dry conditions. Root zones that remain waterlogged tend to get root rot pathogens and can quickly lead to losses. Overly dry growing conditions greatly reduce quality and delay flowering. When watering is necessary, water plants thoroughly, and then allow the soil to dry slightly between waterings. During the growing season apply a balanced liquid fertiliser each month.
Deadheading spent blooms, though tedious, is easily done with a fingernail and will extend the bloom period. Campanulas can generally be grown free of insects and plant pathogens but slugs can damage tender new foliage,
In very hot summer climates Campanulas prefer part shade and will benefit from a summer mulch which helps keep root zone cool. Cut plants back to basal growth if foliage depreciates in summer.
Propagate Carpathian bellflower by dividing the clumps in spring or early summer.