This section is from the book "The Gardener V1", by William Thomson. Also available from Amazon: The New Organic Grower: A Master's Manual of Tools and Techniques for the Home and Market Gardener.
Although it is a good many years since the editor of this magazine brought these famous Stocks prominently before the public in the 'Scottish Gardener,' I do not think they have yet received the attention their great merits deserve, and in many instances their capabilities as decorative plants have not by any means been brought out. No doubt climate has much to do with the perfection they can be brought to, and that it is in dry warm localities like the Lothians they do best. The treatment they receive, from the time the seed is sown till the plants are put out in the borders, has, however, much to do with their success.
In order to get these Stocks to produce an abundance of large spikes of bloom for a long time, the seed should be sown thinly in boxes, the last week of February or early in March, and be placed not, in heat but in a house or pit very little warmer than a common greenhouse, keeping them near the glass. Before they become crowded or drawn in the seedling state, they should be potted into 4-inch pots, and grown in the same intermediate state till they get pretty well established; then they should be put into cold frames near the glass, and by the end of April or beginning of May they will be ready to plant out. The beds should always be in a warm position well exposed to the sun. The soil in which they do best is a rather sandy loam, well enriched with old hotbed manure. They should not be planted closer than 16 inches each way. Managed thus, they do not receive any check at planting-time, and they progress into strong bushy plants, that, in warm localities especially, yield spikes of bloom from a foot to 15 inches long, and continue in flower from early in July till autumn; and I do not know of any other plants that pay better, by giving a fine display of bloom, for any extra treatment they receive.
This strain of Stocks has been well abused by many who have been supplied with seed under the name of East Lothian Stock which has not been true; for the strain is not yet over-plentiful, and purchasers should make sure that they are supplied with the true strain.
To save seed, the single plants should be potted up in October, and planted out when severe frosts are over in spring, taking care to keep the various colours well apart, or cross-fertilisation takes place, and the colours become broken and unsatisfactory.
For greenhouse decoration these Stocks are most useful. By lifting and potting the double ones in autumn, and wintering them in any cool house or pit, they produce a wonderful crop of bloom in spring, and are most useful for arranging among bulbous flowering-plants, Cinerarias, and other spring-flowering subjects. All the varieties, white, purple, and scarlet, are equally valuable for this purpose, and I think their colours are never more pure and effective than in spring. They last a long time, and are very useful for cutting. In this way they can be had in bloom the greater part of the year, and when the strain is true we do not get tired of them. A Florist.