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 garden varieties are very numerous, and now include many different colours, such as pure white, scarlet, rose, purple, carmine, primrose, light and dark blue, mauve, violet, pink, etc. - the double-flowered kinds being most extensively cultivated. Particularly good kinds are White Mammoth, Princess Alice, and All the Year Round, which have fine spikes of pure-white double flowers. Princess May is a fine primrose-yellow variety, and one known as White Christmas is useful for winter bloom, as its white blossoms can be brought to perfection under glass. The Giant Perfection strain of Ten-week Stock is deservedly popular, and may be had in all shades of colour, separate or mixed (fig. 246).
A great trade is done in Ten-week Stock in the seeds, young plants, and in the cut spikes of bloom. For summer work the seeds are sown in February or March in shallow boxes, in rich gritty soil, in the gentle heat of a greenhouse or hotbed. The seedlings are pricked out into similar boxes and soil when large enough to handle easily, and by the end of May, or earlier, are sold largely for bedding purposes. When planted out in rich, moist, but well-drained soil, Ten-week Stocks flower freely during the summer months, coming into bloom by the middle or end of June, and are cut for market.
The "Intermediate" Stocks are also derived from the same parent (Matthiola annua) as the Ten-week Stock, and are particularly valuable for their trusses of scarlet, white, or purple flowers early in the year. The seeds are sown in July and August, and the plants may be wintered in cold frames, or planted out on warm sheltered borders.
The "East Lothian" Stock is a form of the Intermediate, and has varieties with white, purple, and crimson flowers which appear in the autumn after the Ten - week Stocks are over. The seeds are sown in March or April to produce flowering plants at this period.
Fig. 246. - Ten-week Stock.
The "Queen" Stocks, and the Wallflower-leaved Stocks (with green shining leaves) and the Brompton Stocks, are said to be derived from Matthiola incana, a biennial from Southern Europe, the Canary Islands, etc. Of the Queen Stocks there are purple, scarlet, rose, and white varieties, as in the Brompton Stocks, and about 60 per cent produce double flowers. The seeds are sown in June or July in shallow boxes or frames, and the young plants are wintered in cold frames in some places, or planted in warm, sheltered borders in favourable localities. They are chiefly valuable for cut flowers, and choice and well-grown samples often realize remunerative prices.