Artichoke plants continue productive for several years; but, every season, some well-rotted dung, or fresh sea-weed, should be delved into the ground at the winter dressing. It is certain, however, that after a few years, the plants begin to degenerate, the heads becoming smaller and less succulent. It is therefore a general rule, not to keep an artichoke plantation beyond four or at most six years. Scarcely any kind of grub or wire-worm ever touches the roots of artichokes: they !Orin, therefore, an excellent pre parative for a crop of onions, shallot, or garlic. In many gardens a small new plantation is formed every year ; and in this way the artichoke season, which begins in June, is prolonged till November ; those from the old stocks con tinuing till August, when those from the new stocks conic in. If the last gathered be cut with the stems at full length, and if these be stuck among moist sand, the heads may be preserved a month longer.
If some of the large heads on the old stocks be suffered to remain, the calyx-leaves expand, and the centre of the head becomes covered with jagged purple florets, pro ducing a fine appcaravce. The flowers possess the quality of coagulating milk, and have sometimes been used in place of millet. In general the seed is not perfected in our climate. \\Then ripe seed is wanted, it is found use ful to bend down the heads after flowering, in such a way that the autumnal rains may be cast off by the calyx-scales; ;‘nd the heads arc retained in this posture by being tied to stakes.
368. The chard of artichokes, or the tender central leaf stalk blanched, is by some thought preferable to that of the cardoon. When the artichoke quarter is to be shifted, and the old stocks are at any late to be destroyed, the plants may be prepared, after midsummer, when the best crop of heads is over, for yielding chards against winter. The leaves are to be cut over within half a foot of the ground ; the stems as low as possible. In September or October, when the new shoots or leaves are about two feet high, they are bound close with a wreath of hay or straw, and earth or litter is drawn round the stems of the plants. The blanching is pet fccted in a month or six weeks. If the chards are wished late in winter, the whole plants may be dug up, before frost sets in, and laid in sand in their blanched state ; in this way they may be kept for several weeks.
Cardoon.
369. The Cardoon, (Cynara Cardunculus, L.) or, as It is sometimes written, Chardon, is known by nearly the same name in all the European languages. It is a peren nial plant, and is considered as indigenous to the south of • France and to Spain. It so greatly resembles the artichoke as to require no other description. It rises to a greater height than that plant, and becomes sometimes really a gigantic vegetable. It was cultivated in 1683, by Suther land, in the Botanic Garden at Holyroodhouse, Edinburgh; but its use as a culinary plant was known in England pre vious to that period. The leaf-stalks of the inner leaves,
which are fleshy and crisp, afford the eatable part, or chard. They are rendered white and tender by blanching, to the extent of two or even three feet. Cardoons are in season in winter ; they are employed in sonps and stews, and sometimes as a salad, eaten either raw or boiled. In this country they are not much in demand, and the crop is to be seen only in some private gardens, and in a few of the principal market grounds near London.
The best soil for cardoons is one that is light, and not over rich ; but it ought to be deep. Although the cardoon is a perennial plant, it is sown for use every year. For merly the plants were raised on hot-beds, and transplanted in May or June ; but now the seed is generally sown where the plants are to remain. This is not done sooner than the middle or the end of May, lest the plants should be in clined to throw up flower-stems. Some gardeners sow in malt hollows, perhaps three inches deep, and four feet distant from each other every way. Two or three seeds are placed in each hollow, for security ; but only the strongest plant is ultimately retained. Others sow in trenches, prepared as for celery, and keep Ow plants much closer in line, not allowing more than nine or ten inches to each plant ; it is better, however, that they should have more space. The cardoon requires a good deal of water ; and in very dry weather this should be copiously afforded, as it tends both to make the leaves succulent, and to pre vent the inclination to flowering. The young plants that are rejected in either way, may be transplanted, if wished ; but in this case it is useful to preserve a small ball of earth with each plant, and liberal watering is proper.
370. In September, when the leaves are large, they are tied up for blanching, leaving only the top free. This is generally done with hay or straw bands, and a dry day must be selected for the purpose. At the same time a hillock of earth is formed around each plant, to the height perhaps of a foot or eighteen inches ; and this is smoothed on the surface, that the rain may run off, and not fall into the cen tre of the plants. In proportion as they advance in growth, additional bands are added, and the earth is raised higher. When the plants are in trenches, they are gradually earth ed up like celery, without using bands : the earthing is of course begun in July. In either way, the blanching is com pleted in about two months. If severe frost come on, the tops are covered with haulm or long litter. If cardoons be wanted more early, the tying and earthing may be be gun sooner ; but the leaf-stalk will not probably be found so broad and thick as it ought to be.