John Lindley proposed the following classification for the various forms, which includes all yet cultivated: (1) All the leaf-buds active and open, as in wild cabbage and kale or greens; (2) All the leaf-buds active, but forming heads, as in Brussels sprouts; (3) Terminal leaf-bud alone active, forming a head, as in common cabbage, savoys, &c.; (4) Terminal leaf-bud alone active and open, with most of the flowers abortive and succulent, as in cauliflower and broccoli; (5) All the leaf-buds active and open, with most of the flowers abortive and succulent, as in sprouting broccoli. The last variety bears the same relation to common broccoli as Brussels sprouts do to the common cabbage. Of all these forms there are numerous gardeners' varieties, all of which reproduce faithfully enough their parent form by proper and separate cultivation.
Under Lindley's first class, common or Scotch kale or borecole (Brassica oleracea var. acephala or var. fimbriata) includes several varieties which are amongst the hardiest of our esculents, and seldom fail to yield a good supply of winter greens. They require well-enriched soil, and sufficient space for full exposure to air; and they should also be sown early, so as to be well
established and hardened before winter. The main crops should be sown about the first week of April, or, in the north, in the third week of March, and a succession a month later. The Buda kale is sown in May, and planted out in September, but a sowing for late spring use may be made in the last week of August and transplanted towards the end of September. To prevent overcrowding, the plants should be transplanted as soon as they are of sufficient size, but if the ground is not ready to receive them a sufficient number should be pricked out in some open spot. In general the more vigorous sorts should be planted in rows 3 ft. and the smaller growers 2 ft. apart, and 18 in. from plant to plant. In these the heads should be first used, only so much of the heart as is fresh and tender being cut out for boiling; side shoots or sprouts are afterwards produced for a long time in succession, and may be used so long as they are tender enough to admit of being gathered by snapping their stalks asunder.
The plant sends up a stout central stem, growing upright to a height of about 2 ft., with close-set, large thick, plain leaves of a light red or purplish hue. The lower leaves are stripped off for use as the plants grow up, and used for the preparation of broth or "Scotch kail," a dish at one time in great repute in the north-eastern districts of Scotland. A very remarkable variety of open-leaved cabbage is cultivated in the Channel Islands under the name of the Jersey or branching cabbage. It grows to a height of 8 ft, but has been known to attain double that altitude. It throws out branches from the central stem, which is sufficiently firm and woody to be fashioned into walking-sticks; and the stems are even used by the islanders as rafters for bearing the thatch on their cottage-roofs. Several varieties are cultivated as ornamental plants on account of their beautifully coloured, frizzled and laciniated leaves.
Brussels sprouts (Brassica oleracea var. bullata gemmifera) are miniature cabbage-heads, about an inch in diameter, which form in the axils of the leaves. There appears to be no information as to the plant's origin, but, according to Van Mons (1765-1842), physician and chemist, it is mentioned in the year 1213, in the regulations for holding the markets of Belgium, under the name of spruyten (sprouts). It is very hardy and productive, and is much esteemed for the table on account of its flavour and its sightly appearance. The seed should be sown about the middle of March, and again in the first or second week in April for succession. Any good garden soil is suitable. For an early crop it may be sown in a warm pit in February, pricked out and hardened in frames, and planted out in a warm situation in April. The main crop may be planted in rows 2 ft. asunder, the plants 18 in. apart. They should be got out early, so as to be well established and come into use before winter. The head may be cut and used after the best of the little rosettes which feather the stem have been gathered; but, if cut too early, it exposes these rosettes, which are the most delicate portion of the produce, to injury, if the weather be severe. The earliest sprouts become fit for use in November, and they continue good, or even improve in quality, till the month of March following; by successive sowings the sprouts are obtained for the greater part of the year.
The third class is chiefly represented by the common or drumhead cabbage, Brassica oleracea var. capitata, the varieties of which are distinguished by difference in size, form and colour. In Germany it is converted into a popular article of diet under the name of Sauerkraut by placing in a tub alternate layers of salt and cabbage. An acid fermentation sets in, which after a few days is complete, when the vessel is tightly covered over and the product kept for use with animal food.
The savoy is a hardy green variety, characterized by its very wrinkled leaves. The Portugal cabbage, or Couve Tronchuda, is a variety, the tops of which form an excellent cabbage, while the midribs of the large leaves are cooked like sea-kale.
Cabbages contain a very small percentage of nitrogenous compounds as compared with most other articles of food. Their percentage composition, when cooked, is—water, 97.4; fat, 0.1; carbohydrate, 0.4; mineral matter, 0.1; cellulose, 1.3; nitrogenous matter (only about half being proteid), 0.6. Their food-value, apart from their anti-scorbutic properties, is therefore practically nil.
The cabbage requires a well-manured and well-wrought loamy soil. It should have abundant water in summer, liquid manure being specially beneficial. Round London where it is grown in perfection, the ground for it is dug to the depth of two spades or spits, the lower portion being brought up to the action of the weather, and rendered available as food for the plants; while the top-soil, containing the eggs and larvae of many insects, being deeply buried, the plants are less liable to be attacked by the club disease. Farm-yard manure is that most suitable for the cabbage, but artificial manures such as guano, superphosphate of lime or gypsum, together with lime-rubbish, wood-ashes and marl, may, if required, be applied with advantage.
The first sowing of cabbage should be made about the beginning of March; this will be ready for use in July and August, following the autumn-sown crops. Another sowing should be made in the last week of March or first week of April, and will afford a supply from August till November; and a further crop may be made in May to supply young-hearted cabbages in the early part of winter. The autumn sowing, which is the most important, and affords the supply for spring and early summer use, should be made about the last week in August, in warm localities in the south, and about a fortnight earlier in the north; or, to meet fluctuations of climate, it is as well in both cases to anticipate this sowing by another two or three weeks earlier, planting out a portion from each, but the larger number from that sowing which promises best to stand without running to seed.