Campanula is a group of plant species that have bell-shaped flowers. They come in a variety of colors, including white, blue, lavender, pink and rose. Some species reach only 6 inches (15 cm) high, while others reach heights ranging from 4 feet to 6 feet (1 m to 2 m). Campanulas are popular border and garden flowers, and some varieties are suited for container gardening. Campanulas are often used as cut flowers.
Most campanula varieties are biennial, meaning they flower every other year. Sowing campanula seeds every year or for two consecutive years will help to ensure that a garden has campanula blooms each year. Rows of campanula plants should be spaced roughly 12 inches (30 cm) apart, with the same distance between plants in a row. It is possible to propagate campanula varieties by division and by taking cuttings.
Most campanula varieties require a position in full sunlight and should not be placed in crowded areas. Tall varieties will most likely require support to prevent damage and breakage from strong winds. Campanulas prefer rich soil. Fertilizers such as manure or homemade compost are ideal and should be dug in around each plant in the spring.
Among the tallest of the campanula varieties is the chimney bellflower, growing up to 6 feet (2 m) high. The chimney bellflower produces long stalks of flowers that are usually white or pale blue. The flowering period lasts approximately six weeks. If blooms are removed as soon as they begin to pale and fade, the flowering period may be extended for approximately two weeks.
The Scottish harebell, campanula rotundifolia, sometimes incorrectly called an English bluebell, is one of the most popular campanula varieties. Its flowers range from a violet-blue to pink or white and generally consist of five connected petals that form a bell shape. It grows naturally in grasslands in North America, Britain and other parts of Europe. Adult plants can grow tall enough to hold their own against tall grass.
Canterbury bells produce large flowers in white, blue and purple. The blooming stem reaches roughly 2 feet (60 cm) tall. When planted among other plant varieties, such as phlox, Canterbury bells make an exuberant and striking display. Peach bells grow up to 3 feet (90 cm) high and produce long, slender flower stems. The flowers of the peach bell are blue, white or pale lilac and are looser than those of the harebell varieties. Multiple blooms appear on each stem, and hybrid varieties are available with double blooms.