Bell flower is the common name of a group of plants distinguished by their bell or star-shaped flowers. Known as campanula, these flowers range in size from 6 inches to 4 feet and can fill any niche in your garden. Bell flowers originated in Scotland, where they are known as bluebells or harebells. Bell flowers have since naturalized throughout Europe and North America. Some bell flowers can become invasive, spreading by stolons, and should be planted in areas where they can sprawl. Flower colors are traditionally purple or blue but you can now find cultivars with white or pink flowers.
Bell flowers can be planted in any soil type as long as it is fast-draining. Use bell flowers in rock gardens, woodland gardens, edging for flower borders and in the back of borders.
Starting Bellflowers from Seed
Sow annual bell flower seeds in the spot you want them to grow. Scatter the seeds over the soil and firm them in using the back of a hand trowel.
Start perennial bell flower seeds 6 to 8 weeks before the last frost date in your region.
Fill seed starting flats with sterile seed starting soil. Moisten the soil before sowing seeds.
Scatter bell flower seeds over the soil. Cover the seeds with 1/4 inch of sterile seed starting soil or compost.
Place the flat in a bright, warm room out of direct sunlight. Seeds should germinate in 6 to 20 days depending on the cultivar.
Water your seeds from below by placing the seed starting flat in a larger container filled with water. Remove the seed starting flat when the soil is moist. Keep the soil moist but do not allow it to become soggy.
Transplant your seedlings into individual pots when they are large enough to handle without damaging the stems, usually after they have grown their first true leaves.
Make your own seedling soil mix out of 2/3 sterile seed starting soil and 1/3 compost/sand mix. The compost/sand mix should be a 50/50 mix.
Place your seedlings in a bright room where temperatures stay above 50 degrees F. Keep the seedlings out of direct sunlight. Keep the soil moist but do not allow it to become soggy. Watering from below will help prevent damping off. Seedlings are ready to be planted outside when all danger of frost has passed.
Choose a sunny spot with that provides afternoon shade with fast or well-drained soil.
Dig a hole just deep enough to accommodate the bell flower's roots. Spacing varies with cultivar but as a general rule plants should be 12 to 18 inches apart.
Give your bell flower 1 inch of water during its first year. Established bell flowers do not need supplemental watering unless your region is going through an extended period of drought.
Deadhead (remove faded or dead flowers) promptly to extend flowering. Deadheading will encourage some cultivars to flower again later in the season.
Divide bell flowers when the center becomes woody or dies. Dig the plant up and cut into sections. Discard the woody center and replant the vigorous outer growth. Make sure each section has a substantial number of roots.