Biennial then Short-Lived Perennial Truly beautiful, old-fashioned and very sought after, biennial Campanula ''Bells of Holland'' or Canterbury Bells are a must-have in your garden. Lush, fresh green rosettes of foliage send up tall stems of large blue, purple, pink or white goblet-shaped flowers in their second season. If cut back after flowering they will put on a fresh flush of foliage and give you more flowers in the following season or two. Dead-head for a continuous supply of flowers for months. Sun, semi-shade, well-drained soil that doesn't dry out too much in summer. Self-seeds politely and who wouldn't want them to! 75x45cm approximately. Punnets of 6 plants.