A Treatise on the Culture of the Vine and, and the Art of Making Wine/Part 1/Chapter 4
CHAPTER FOURTH.
Of the height of Vines and of their Pruning and Supports.
FROM the dwarf vine, pruned to within a few inches of the ground, to that which overtops the elm which it clings to for support, there is every variety in the height of vines.
Those which are supported by trees, are common in Italy and Spain, and are occasionally met with in some of the most southern districts of France. Some are supported by poles, to various heights; and others are allowed to trail their branches on the ground, or to support them as their strength or direction will allow.
The highest kinds of vines, not supported by trees, are frequently trained on poles, joined in a sort of trellis, to the height of from seven to ten feet. The stocks of others, are kept from two and a half to four and a half feet in height, and supported by poles of the height of six feet.
In situations, exposed to high winds or storms, three of these poles are frequently joined together at top, forming a triangle, to which the shoots of various stocks are attached, and are thus mutually supported, and the grapes preserved from being bruised, or destroyed. This method of culture it very common, from the shores of the Mediterranean, to the neighbourhood of Lyons, and is the method practised at Ostie Rotie, and Condrieu, where it is directed with much care.
In general, as we approach a colder climate, we see the vines reduced in their dimensions.
The proportion which it is necessary to preserve between the sap circulating in the plant, and the heat which is to modify that sap, will not admit of a larger growth; besides, it is only near the surface of the earth that there is a sufficient degree of heat to ripen the grape. In warmer climates, a vine is capable of bringing to maturity a large portion of fruit, and its height, and its branches, may be proportionably increased, but there seems, in this respect, a bound which may not be passed with advantage. It is not only because the fruit of these vines, supported by trees, is, by their foliage, shaded from the rays of the sun, that they yield wine of as inferior description. It is the nature of the vine, to absorb moisture by its leaves, in much greater proportion than, by its roots; and this unmeasured foilage continues to supply a quantity of sap, which circulates without elaboration, and is rather employed in the formation of wood, and the grapes, consequently, contain an aqueous fluid, which it is impossible to convert into a wine of good quality.
Trees which are pruned, never attain the size and strength of those, the branches of which grow old with them, because, by pruning of so much of the wood, a larger proportion of the sap is forced into the fruit, than would naturally flow to it. Qualities are thus produced in fruits, which, naturally, they would not attain; and there are two sorts of maturity, that which nature, left to herself, gives, which is sufficient to propagate, by seed, the plant in its natural climate, and that which art procures, in carrying the fruit to a higher degree of perfection, at the expense of the other parts of the tree. In the vine, there way be said to be a third sort of maturity; that which gives, in a high degree, the principles on which depend the qualities of the wine made from its fruits; for these are often masked by a taste which is unpleasant to the palate, and are frequently wanting when the palate is most flattered by the fruit.
Thus, the grape may be brought to a tolerable degree of perfection, as a fruit, in a much colder climate, than it would naturally grow, and in a climate where, naturally, it would be slender shrub bearing sour grapes; it may be brought to yield fruit, possessing, in a high degree, the vinous principles; but it does not appear, that, in the climates most favourable for it, and where its dimensions are greatest, it ever naturally brings its fruits to that state of maturity, in which they would undergo the vinous fermentation. For the attainment of this object, it is necessary, in all cases, to reduce the size of the plants, and concentrate that sap, which would tend to the production and enlargement of the wood, to the perfecting of the fruit. This end cannot be obtained, even in the warmest climates of France, in a plant of greater height than four and a half feet, including the mother branches; and perhaps no cultivator, who is not regardless of the quality of his wine, should allow it to exceed this height. But even in countries, enjoying every advantage of climate, and vineyards, possessing the most suitable soil and situation, the cultivator sometimes finds it his interest, to confine its growth to the dimensions more common in less favourable climates. Thus in the best vineyards of Medoc, producing the claret wines, the vines do not exceed eighteen inches, or two feet, in height. The best vines of Sicily, (those of Mr. Wodehouse), are also of a dwarf size, and are confined to the production of four bunches each.
If the cuttings, which form a new plantation have been well selected, and the operation of planting, conducted with care, they will have sent out, at the end of the first year, a shoot from each of the eyes left above the surface; and, if the wood is sufficiently ripe, these must be pruned; but, if they have not attained sufficient consistence, the pruning must be deferred till the following year. The object of pruning, in this case, is to concentrate the juices of the plants, which would run the formation of crowds of useless shoots and leaves, to the strengthening or forming of one stock, or stem. In the first pruning, the shoot from the uppermost knot, or eye, should be entirely removed, and the other cut above the first eye. In the second year, if it be destined for a vine of from four to five feet in height, it should be pruned above three shoots, and the others removed close to the stock; for a lower vine, two shoots are sufficient; and for a dwarf vine, one, and this should be the lowest. In all cases, only the lowest eye should be left to each shoot.
In the third year, an additional eye may be left on each of the mother branches, which still ought to be confined to three, and should rarely exceed four, even in its most advanced state. Two mother branches are sufficient for the lower vine; that is, one which is allowed to grow from two and a half to three and a half feet in height; and it is only from the trunk, or stock of the dwarf vine, thus the fruit-bearing branches should issue, those which are lowest being always preferred, if their inclination is not such, as to expose the fruit to the contact of the ground.
At the fourth year, a well planted vine has acquired strength to give fruit—two eyes may be left on two or three of the strongest shoots. The pruning in the fifth season, still requires particular management; two eyes should be left only on the strongest of the new wood, and that which has less vigour, should retain only one; the whole number of the branches of young wood thus left, should not exceed five. The young plant has now become a made vine.
The care of the cultivator, must not, however, be relaxed;—the same principles which have hitherto directed him, should guide him in future;—but the plant, having acquired more vigour, will require more minute attention in the pruning.
There are circumstances by which he must be guided, in leaving a greater quantity of bearing branches, or retrenching their number: these are, the nature of the climate, the exposure, the nature of the soil, the vigour of the plant, the quality of the wood formed the preceding year. The age of the vine ought, also, to be considered, and the kind to which it belongs; one kind, is famous for ripening a large quantity of grapes; another, is capable of bringing only a small quantity of grapes to perfection. The vine, too heavily charged, is soon exhausted; too lightly, it yields little but wood.
In the warmer climates of the south of France, a vine of four and a half or five feet in height, and proportionally distant from other plants, may support, on each of its three or four mother branches, five or six young branches; and on each of these, from four to six eyes may be left without inconvenience. The lower vines, which are more closely planted, and have only two mother branches, are sufficiently charged with two or three shoots on each; and on these, two or three eyes may be left according to the strength of the wood.
The dwarf vine is not forked, and the plants are still closer; three or four shoots are sufficient to leave on it, and one or two eyes, on each of these, will charge it in proportion to its strength.
The necessity of adhering to a system of pruning, which will equalize, as much as possible, the fruit which a vine is allowed to bear to its strength, is so great, that there are few instances of vines being let. The interest of the farmer, might induce him to leave a quantity of fruit on the vine, which would destroy its future capacity for bearing. Thus, to charge a plant as heavily as it will bear and to charge it to death, are synonimous expressions.
An old vine requires the same care and attention, as when it was still in its infancy; it requires to be pruned close, and the old wood frequently renewed; this makes shoots which spring from the bottom of the stock, of great value, although at first sterile. Not only age, but the numerous accidents to which the vine is subject, make this measure necessary. When a vine is so injured by frost, that an after budding cannot be reckoned on, the old and new wood is cut close to the stock. A vine should also be pruned above, when its yellow and sickly appearance indicates that worms hate attacked its roots. If, on the contrary, in the year preceding, the abortion of the flower has disappointed the hopes of fruit, and the sap has been employed in forming shoots of unmeasured length, there is nothing risked, in leaving a larger quantity of bearing wood, and charging it amply with fruit; as, if a little exhausted, it can be pruned proportionally shorter in the following year. In dry seasons, the vine makes little wood, and should be pruned short, as also, if the winter has been severe. If the wood and the fruit buds have been in part frozen, they should not be hastily removed, there is till room to expect a harvest from the after buds. When the weather has become mild, the branches which have suffered, may be removed above the uninjured buds.
In the operation of pruning, care should be taken, that the instrument of the workman be sharp, that the wood may not be bruised. The cut should be an inch from the nearest eye, and sloping from the side opposite to it.
A question which divides agriculturists. is, whether it is more advantageous to prune in autumn, or in spring; and this is a question which each cultivator must determine for himself, by the nature of the climate under which his vines are situated. It is rather a question to be determined by circumstances, than by a general rule. If, on the one hand, the vine is pruned in autumn, the wood may be still unripe; and it is an observation, whose truth has been confirmed by long experience, that a vine, pruned before the wood has reached maturity, is sure to perish in the course of three or four years. If the operation is delayed till the complete maturity of the wood, it has much to fear from the severity of the winter, as, from its open and spongy nature, it is very susceptible of injury from frosts and moisture.
If, on the other hand, the operation is delayed till spring, the frosts so frequently encroach upon the time of vegetation, that in shunning dauger from these, the sap commences to circulate, and weeps from the wounds, to the great impoverishment of the plant. The autumn pruning, too, hastens the shooting of the wood the following year, and in late kinds, brings the fruit to an earlier maturity; and, as the interest of the cultivator is, to have all his kinds ripe at the same period, this may be so managed, as to be subservient in procuring a simultaneous ripeness among the varieties. It is, however, the most common practice, to defer the operation till spring; and, in all cases, it is most important, that the weather should be settled, and fine.
Various supports are used for vines, as their height may require, as the value of, their produce may make every thing important, which can contribute in any way to their improvement. In many places, where the ground is dry, supports are altogether dispensed with for low vines, though nature, by giving tendrils to the upper part of its branches, seems to indicate the dependence of the support. It is strongly recommended, to train the vines on a trellis; but in wine countries, in general, the wood is so expensive, that a trellis is seldom seen supporting any but vines of the highest stature, not supported by trees. The common practice, is to fix a pole between two plants, to which the branches are fastened, by twigs of osier; and too little care is generally bestowed, in giving a proper direction to the branches.
The natural course of the sap is vertical, and when this is assisted by the direction of the branches, it rushes with astonishing force to the extremities of the young shoots, where it is wasted in the production of new and useless wood; when, on the contrary, the branches are fixed horizontally, or even in a semicircular position, its natural course is interrupted and it is the better elaborated, as it circulates with less vehemence.
The direction in which the trellis extends, is not a matter of indifference. Where the vines are subject to be injured by frost, their arrangement to face the east, would only expose them to the greater danger from the rising sun. But, when exposed to the south, the frost has already yielded to the heat of the atmosphere, before they receive his direct rays. In hotter countries, again it would appear necessary, rather to protect the fruit from the burning influence of the sun's rays, as at Madeira, where the vines are trained over a low horizontal lattice work, under which, the fruit ripens in the shade.
The vines being thus pruned, and attached to their supports, the first of the fine weather has has scarcely appeared, when the buds have already begun to burst forth. But the labour of the cultivator has not yet terminated. Three distinct operations are described, by which the branches are successively stopt in their growth, relieved from their useless shoots, and in part, from their leaves. But these are operations which ought not, in all circumstances, to take place; they depend not only on the nature of the climate, but on the state of the weather. Thus, in a climate rather mild than warm, as in a great part of France, the vine-dresser sees the unmeasured length of the shoots, and fears that all the sap will be converted into wood, and that the fruit will be deprived of the share necessary to its maturity. To cause the reflux of the sap towards the grape, he cuts off the extremity of the shoot; this has the wished for effect, but it also escapes in numerous small shoots through the lower eyes, and these are from the same principle, in the same manner, lopped off. When these operations are performed in a colder climate, or a wet season, they are attended with excellent effects, though not in the manner which the operator generally conceives.
The vine, absorbing by its leaves, a much greater portion of its nutritive principles than by its roots, these leaves and branches, if left, would absorb a much greater portion of sap than the heat would elaborate, and hence would result the immaturity of the grape. The same principles will not apply in a hotter climate, and a drier season and soil; and hence, in the most southern districts of France, and in Spain, Italy, and Sicily, these are are not performed.
A third operation, the removal of the larger leaves, when the grape has attained almost its full size, has, besides the above, another object in view, which is, the exposure of the bunches to the ripening influence of the sun's rays. This is only necessary, or advantageous, in colder climates, it being seen above, that it is in some cases advantageous to ripen the grapes in the shade.
Where these operations are advantageous, much care and judgment is necessary to direct them. The branches should never be shortened before the vine has flowered, nor indeed before the grapes are formed
The neglect of this precaution, by causing the reflux of the sap, and carrying a superabundance of it to the flower, at a delicate crisis, is one of the most frequent causes of its sterility. If too great a number of the leaves be removed, the grapes dry and rot, without reaching maturity; and this is not all, for the shoots which are still green, cease to ripen; and the buds, not having received, on the part of the leaves, their complement of vegetation, are either entirely barren the year; or, if they open into flowers, are unproductive of fruit.