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.
The trade in Camellias is not nearly so extensive as in former years, although one or two nurserymen still make a brave show of flowering plants during the winter season. At one time growers for market cultivated Camellias in almost any kind of glass structure, and in old establishments one may still see here and there some fine old specimens in tumble-down lean-to houses. Late vineries were a favourite place for housing the pot plants during the winter months, while during the summer months they were placed in the open air in the same way as Azaleas. For the purpose of the cut-flower trade the old Double White Camellia (alba plena) is unrivalled, and is largely used by florists. The blooms are cut quite close to the base without a stalk, and are packed in shallow boxes on a layer of cotton wool, and realize from 1s. to 1s. 6d. per dozen flowers. Of late years, however, owing to the more extensive use of the white lancifolium and longiflorum Liliums, the Double White Camellia has lost its former importance.
The culture of Camellias is quite simple. They flourish in almost any good soil of a loamy nature, or a mixture of loam and peat, and require very little heat, even to force into early blossom. During growth the roots must be supplied with plenty of water, and until the flower buds are well set the foliage must be frequently syringed to keep it clean and glossy and free from attacks of insects and black fungus.
To keep plants in good shape it is necessary to thin out twiggy shoots in the centre after the flowering period, and thus induce new growths outwards and lower down the main stems. It is unnecessary to pot the plants every year, some lasting for several years in the same pots. To keep them up to the flowering mark, however, weak liquid manure should be applied during active growth. Camellias may be propagated by cuttings of the nearly ripened young shoots inserted in sandy peat and loam, and plunged in bottom heat. They are, however, increased more readily by grafting - the scions of choice varieties being united with stocks of the commoner single-flowered varieties. In this way large numbers of plants are raised on the Continent. Some firms also make a speciality of raising seedling varieties.