This section is from the book "Commercial Gardening Vol2", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
Everybody knows and admires the Canterbury Bell, which is an imposing hardy herbaceous biennial of pyramidal habit of growth and profuse flowering. The "cup and saucer" section of these flowers is perhaps the more attractive and is distinguished by the varietal name of Calycanthema. The shades of colour in both sets include white, blue, mauve, pink, etc, and there are also double-and single-flowered varieties, all of which may be raised from seeds sown during the spring months either in frames or in the open. It should be stated that, however carefully the seeds are harvested or grown, a certain percentage will not be true to their kind, whether of single or double varieties.
The plants grow with considerable freedom in any good garden soil, and where cultivated by the acre as a root crop are productive of a good return. Potted in September or October and gently forced, the Canterbury Bell is useful also a pot market plant for decoration.
The Peach-leaved Campanula (C. persicifolia) in blue and white varieties is also useful in much the same way. It is, however, a true perennial, delights in cool spots and moisture-laden soils, and abhors drought.
[e. h. J].