The common methods of forcing early grapes are to train the vines under the roof near the glass, or on small frames against flued walls; but to both these practices Mr. Acon finds great objections: to the former because it renders the house too dark, and exposes the young and tender branches to the pernicious effect of blasts of cold air rushing through the interstices of the panes; and to the latter, because the heat of the flues is apt to scorch the branches, and in consequence to destroy the crop,—excessive heat in the one case producing the same injurious effects as excessive cold in the other. The following are the two modes by which Mr. Acon obtains his very early and his very late grapes. For the early crops a house is used, of which the back wall is 9.6 feet in height, and the front wall 3 feet, the roof forming an angle of about 30 degrees. It is heated, from the absolute necessity of employing an atmosphere of unusually high temperature, with two flues that pass along the middle of the house, and return in the back wall; a fire-place being built at each end of the house. Forcing begins on the first of September, and the fruit begins to ripen the first week in March. The vines are trained upon a trellis, fixed over the flues, in the centre of the house, and also upon the back wall; but none are allowed to obstruct the light by occupying the roof, until about six weeks after the forcing has commenced, when some new shoots are introduced and trained to the rafters. The form of this house gives it a peculiar advantage, in presenting a greater surface for the growth of vines than can be derived from any other plan; the trellis which is placed over the flues is nearly equal to the whole roof, without being in any degree injurious to the plants trained upon the back wall. The vines are planted in the inside of the house, but in such a manner that the mould in which they grow is not heated by the fire-places of either flue. The usual mode of exposing the main stem of a forced vine to an extremely low temperature in the external air, while the branches are stimulated by a very high temperature in an entirely different atmosphere, is very properly objected to. Nothing, in fact, can be more injudicious than such a practice, in cases where very early forcing is required; for it should be borne in mind, that although the absorption of the elements by which the proper juices of a [p161] plant are elaborated, and brought into the state under which they appear in the fruit, and in the secretions of the plant, is carried on by the leaves alone, yet that all these juices have, in the first instance, to pass along the vessels of the stem before they reach the leaves; and that the whole of the bark of a tree is, rightly considered, a leaf of a particular description, formed of the same kind of tissue, and exercising the same functions, and undoubtedly producing a powerful effect upon the motion of the fluids of the branches, with the vessels of which it is elaborately and intimately entangled, from the core to the circumference. No argument can be necessary to show that an equal action of the vessels of a plant is indispensable to the due maintenance of the vegetable functions in a healthy state, and that this is not to be maintained by exposing the main stem and the extremities to an atmosphere and temperature entirely different. Such irregularities do not exist in free Nature, and she will not submit to them when in fetters.
In pruning vines for early forcing, as little wood should be employed as possible. Mr. Acon stops the shoots one joint above each cluster, and has no joint without a bunch. When the crop is over, and the wood perfectly matured, the branches should be laid near the ground, and shaded till the recommencement of forcing. In short, they should be placed in a condition as nearly as possible resembling the gloom and cold of winter. If this process be well managed, the vines will alter their natural habits, and instead of budding with the spring, their vegetation will naturally commence at the period at which they have been accustomed to be stimulated.
For late grapes, a house of a different construction is employed. The back wall is 12 feet high, the front wall 112 foot, and the roof lies at an angle of 45 degrees. The heat is supplied by a single flue passing along the middle of the house. The sorts best adapted for late forcing are the Muscat of Alexandria, the St. Peter’s, and the Black Damascus; all other kinds wither prematurely. This house is generally shut about the middle or end of May, as soon as the bunches become visible. The vines are trained on a trellis near the glass. Till they are out of blossom the air is kept very warm, a point to which much importance attaches, because it is during this period that all the branches that are to bear fruit in the succeeding season are produced. In a high temperature, the branches will grow more compactly, and [p162] will be more regularly matured than in a low temperature, in which the wood is apt to become excessively luxuriant, and not to ripen well. Great attention must be paid to this point. As much air as possible is introduced into the vinery during the summer; but as the autumn advances, more caution in this respect is observed. The fruit should be perfectly coloured at the approach of the dark season; for if the colouring be deferred too long, the berries will never acquire their proper flavour. Great care must be observed to remove daily such berries as are inclining to damp, or the whole crop will soon be spoiled. This should be particularly attended to; for the contagion of what gardeners call damp, arises from the growth of minute fungi which vegetate upon the epidermis, and spread during the autumn with alarming rapidity from bunch to bunch.
The pruning of vines for late forcing is the same as has been already explained. When the crop is gathered, the house is unroofed for a short time, in order to expose the branches to a low temperature, and to the degree of humidity necessary to replenish their vessels, which have been drained by the dryness of the climate in which, when forced, they were necessarily kept.
By the means above described, a regular supply of grapes is secured through the year. The late-house crop lasts from the middle of January to the end of March; it is succeeded by the first crop in the early-house, which carries on the supply into May, and it is continued by the grapes on the rafters in the same house until the vines in the pine stoves, which are forced early in January and February, produce their crops. These continue bearing through the summer, when a vinery, of which the forcing commences about the end of March, furnishes the supply till the late-house fruit is ready in January.
Upon the whole this may be considered a most instructive and valuable communication.
II. On the Varieties of Cardoon, and the Methods of cultivating them. By Mr. A. Mathews. [◊]
Who does not wish to read of the cardoon; of that prince of vegetables, whose praises have been sung or said by all cooks and gourmands, from the fastidious Périgords and Cardellis of the French cuisine, down to the more homely Rundells and Glasses of our English kitchens; whose virtues are so marvellous as to be credible upon no less authority [p163] than that of the sage gastrophilists aforesaid. To restore unwonted vigour to old age, and new elasticity to youth, are the most modest of its attributes; the magical broth with which the veins of Æson were replenished by the cunning Medea, was doubtless prepared from the cardoon; and the story itself is probably a sort of figurative record of the skill of the fair enchantress in cooking this delicious vegetable, which was well known to the Grecian gastronomes under the name of κακτος; but this we throw out merely as a suggestion. Upon preparing herbs thus potent for the table, cookery has exhausted all its skill; to dress a cardoon is declared, by the highest authority in the art, to be the surest test of a skilful cook; and one of those invaluable acquirements which, to borrow the words of a writer not less celebrated for his powers of composition than of cooking, “raises cookery to the rank of the sciences, and its professors to the title of artists.” Our good forefathers, indeed, “could not find the true manner of dressing cardoons,” and were content to eat them raw “with vinegar and oyl, pepper and salt, all of them, or some, as every one liketh for their delight;” which, considering that this vegetable is both bitter and astringent in a high degree, does not argue much for the delicacy of palate of our ancestors; little did they dream of the savoury preparations that modern art has devised by the aid of Espagnole, consommé, blancs, tammies, marking, masking, and all the mysteries of the stew-pan.
Four varieties are here described, of which the Spanish cardoon is the most common, and the cardon de Tours the best.
They are cultivated, like celery, in deep broad trenches, well manured and watered. When the plants are nearly full-grown, which will be about the end of October, a dry day is to be chosen for performing the operation of blanching them, which is thus effected:—