About Bellflowers
Bellflowers (Campanula) are a diverse genus of perennials producing charming bell-shaped or star-shaped flowers in shades of blue, purple, pink, and white. They range from low ground-hugging varieties to tall, stately spires reaching 3 feet or more. Hardy in zones 3 to 8, bellflowers are classic cottage garden plants that bloom from late spring through midsummer and attract bees and hummingbirds.
Starting from Seed
Start bellflower seeds indoors 6 to 8 weeks before last frost. Sow on the surface of moist seed-starting mix and cover with a very fine dusting of vermiculite — seeds need some light to germinate but must stay moist. Maintain soil temperature at 60-70°F. Cover with a humidity dome. Germination takes 14 to 21 days. Some perennial campanula varieties benefit from cold stratification — refrigerate seeds in a damp paper towel for 3 to 4 weeks before sowing. Bellflower seedlings grow slowly; be patient.
Planting Out
Transplant when seedlings are 3 to 4 inches tall and all frost danger has passed. Choose a spot with full sun to partial shade. In hot climates (zones 7+), afternoon shade helps prevent stress. Space plants 12 to 15 inches apart in rich, well-drained soil with a pH of 6.0 to 8.0. Amend heavy clay with compost to improve drainage.
Watering & Feeding
Keep soil evenly moist but not soggy. Bellflowers prefer moderate, consistent moisture. In early spring, apply a balanced slow-release fertilizer. Add a thin layer of organic mulch around plants to retain moisture and keep roots cool. Avoid heavy, wet mulches that sit against the crown.
Ongoing Care
Deadhead spent flowers to encourage reblooming. In late winter, cut back dead foliage before new spring growth emerges. Note that perennial campanula can take 2 or more years from seed to reach full blooming size — the wait is worth it. Divide established clumps every 3 to 4 years to maintain vigor. Bellflowers combine beautifully with hollyhocks, dianthus, and primroses in cottage garden borders, and their vertical flower spires provide wonderful contrast to mounding plants.