The Campanula plant genus is very large, and includes species that are Hardy Perennial, Hardy Biennial, and Hardy Annual in nature.
One thing that Campanula plants have in common, is that they all bear bell-like flowers. These are usually of blue or white.
Harebell / Bluebell (Campanula rotundifolia) by Brewbooks
Smaller species, can be used in a rockery, whereas larger members of the Campanula genus can be used anywhere in the garden.
Peach leaved bellflower (Campanula persicifolia) by Suneko
Some of the common names of Campanula garden plants include Bellflower, Peach Bells, Harebell, and Canterbury bells. They usually flower in the spring or summer.
Campanula rotundifolia (Harebell / Scottish Bluebell), photograph by Anne and David; CC.
Campanula portenschlagiana (Wall Bellflower), photograph by Babij; CC.
Campanula americana (American Bellflower / Tall Bellflower), photograph by Joshua Mayer; CC.
Campanula poscharskyana (Serbian Bellflower / Trailing Bellflower), picture by Staudengärtnerei Forssman; CC.
Seeds of the Campanula plant should be sown on the surface in the early spring.
If growing bellflower and similar garden flowers from seed indoors, then they should be prepared about ten weeks before putting out.
They require two to three weeks to germinate. For gemination, Campanula should be grown in light, at a temperature of between 15 and 20°C (59 to 68°F).
The seedlings of bellflower should then be planted at a spacing of about 20 cm (8 inches; small varieties) or 40 cm (16 inches; larger varieties).
They should be located into an area of the garden that has full exposure to the sun, into a pH neutral soil, in the early spring.
Campanula plant species such as bellflower and Harebell require feeding in the spring, and regular watering in dry periods.
It is best to dead-head Campanula flowers to prolong their blooming season by encouraging further flowers.
I hope that you enjoyed this guide on Campanula. You may also enjoy the following Gardener's HQ growing guides: How to grow Phyteuma, Brimeura plant, Roscoea plant, and Platycodon plants.