Set plants 1 to 2 feet apart, depending on the ultimate size of the species or cultivar you’ve chosen. Plant in fertile, well-drained but moisture-retentive soil, high in organic matter. Campanula will thrive in sun or partial shade.
A light winter mulch is beneficial. In areas where slugs and snails are a problem, an appropriate poison bait is recommended, as Campanula foliage is a favorite of these pests. Taller species or cultivars may require staking. A balanced fertilizer, applied each spring, will promote lush growth, and removal of spent flowers will promote additional flower production.
Zones 3 to 9.