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.
So called, doubtless, because of their hardiness and amenability to cultivation in the open air. The original wild species (Dianthus Caryophyllus). from which all the border types have been evolved by the gardener, is a hardy plant indigenous to this country. It is usually found on old walls and ruins, its root fibres tightly wedged in mortar crevices. From this it may be inferred that the carnation is a lime-loving subject, and the deduction is reasonable and correct. The Perpetual Flowering Carnation is dealt with in the following section.
The border Carnation produces at or near the ground level prostrate evergreen tufts of growth, and in this way differs unmistakably from the "perpetual" types which are usually of a tall habit of growth and produce successional growths or shoots upon their stems.
Within the limits of the border section proper a wide range of classes is found: "selfs" of many shades, as crimson, rose, scarlet, white, pink; "fancies", which have a yellow, white, cream, or apricot ground, and petals marked by one or more colour shades or a suffusion of them. The " Picotee", both white and yellow grounds, falls naturally into the border section of these flowers, as do also the "Flakes", "Bizarres", and others of the show class so beloved of old-time florists.
Culturally, and for exhibition work in particular, the whole of these require to be pot-grown, and flowered either in a cold, well-ventilated greenhouse, or, what is almost equally good and a hundred times cheaper, an improvised canvas-screened shed. In such circumstances the flowers expand more gradually, and are more enduring. It is important that the screen be not sufficiently heavy to obscure much light, which would speedily out-characterize the flowers. What is needed is a roof screen alone, to keep off hail, rain, and the great heat of the moment, the sides being quite open. For garden decoration the plants should be massed together in beds or groups of one colour, at all times keeping the high-coloured cerise shades apart from those of pale pink or salmon.
Generally speaking, in the matter of soils the carnation prefers a rather heavy loam, so fibrous and conservative of texture that it is not possible to reduce it readily to dust-like particles. The lightest and sandiest of soils the carnation plant abhors, and, as a fact, it is shortlived in them. The heavier soils should be freely charged with old mortar rubble or burnt lias clay - the latter excellent where procurable. Bone meal at the rate of 6-in. pot to 2 bus. of soil is a good and lasting fertilizer, but should be mixed with the soil some few weeks in advance of being required.
Commercially, the Border Carnation resolves itself into two or three excellent lines, viz. specializing in high-class strains for the raising of layers, the production of hand-fertilized seeds which are rarely produced in sufficient quantity, and that rougher outdoor method of producing layers by the thousand. For the last purpose we strongly recommend the old Crimson Clove, White Clove, Raby Castle, Duchess of Fife, Gloire de Nancy, and Countess of Paris, while of more recently raised sorts Daffodil and Cecilia, yellow; Lady Hermione, salmon; Trojan, white; and Robert Berkeley and Cardinal, scarlet, will take some beating. Half an acre devoted to these flowers in the six first-named varieties would yield a big return, and in suitable land free of wireworm this crop could hardly be surpassed. Layering would be the heaviest item on the expenditure side, which would, however, be well met by the sale of the flowers. [e. h. j].