Campanula flowers (Campanula spp.) are a group of flowering perennials native to the Northern Hemisphere. Also known as bellflowers, these plants are highly desirable for their large, bell-shaped flowers that come in shades of blue, purple, pink and creamy white. The size of the plant varies between only 4 inches tall and over 4 feet tall, depending on the species and cultivar, with a maximum spread of 3 feet. Campanula flowers are hardy to United States Department of Agriculture zone 3 and are low-maintenance plants, according to the University of Illinois.
Choose a sunny or partially shaded area for your campanula flowers. Well-draining soil is best for these plants, according to the University of Maryland, so avoid planting in a depression or where standing water collects.
Sow campanula seeds early in the spring, when there is no danger of frost. Place the seeds between 12 and 18 inches apart, and cover them with a fine layer of soil.
Water at least once a week. While these plants can tolerate brief periods of drought, according to the University of Illinois, they grow best when the soil is kept moist.
Feed your campanula flowers with a balanced (10-10-10), all-purpose fertilizer in the spring when growth appears and again in the summer when the first flush of flowers has faded.
Deadhead (remove spent flowers) frequently to encourage re-blooming. If properly deadheaded, campanula flowers will bloom from spring clear through the end of summer.