The next thing in order is that of laying out the vineyard, in which it will be desirable to consider what distance apart the vines are to be planted. This matter of spacing the vines is one about which there is still considerable disagreement; and the question as to whether they should be planted near to one another, or far apart, is yet unsettled. But the truth is no inflexible rule can be laid down, as the climate, the soil, and the "cepage" all exercise a controlling influence. It seems to be generally admitted that in the warm districts the vines should be planted farther apart than in the cooler regions.
In a hot climate the vigour of the plant is increased by the great amount of light and heat which it receives. The must will be too strong, therefore, and it is only by planting the vines at a greater distance apart than usual, and also by pruning very long, that the resulting wine will be rendered sufficiently light in strength. In a cooler region, on the other hand, where the vigour of the plant is less, the crop on each vine must be reduced by short pruning, so as to increase the percentage of glucose in the must and ensure a good wine. And where the size of the plant is lessened by this method of pruning, the vines must be placed closer together in order to make use of all the available soil. This latter itself has also to be thought of in this matter of spacing the vines. In a rich soil, where the vigour of the plant is increased, the vines should be placed farther apart; in a poor soil, on the contrary, they should be planted closer together.
Mr. Francois de Castella, formerly Expert to the Board of Viticulture, the author of The Handbook on Viticulture for Victoria, and who is now the proprietor of the Tongala vineyard, in an instructive article on viticulture in Victoria lays down the following rules with regard to the spacing of vines : - "There is for each locality, with the same conditions of soil and climate, a certain distance, which we may call the optimum, at which vines will thrive best; if this distance be increased they will not improve, and may even deteriorate. Unless this be a distance which cannot conveniently be worked by horse labour, it would evidently be a waste of land to plant any wider, and would entail the use of unnecessary labour for its cultivation. It would be just as foolish to plant vines any closer than this, as it would give unnecessary pruning, disbudding, tying up, etc. - that is, if the climate be such that grapes will ripen satisfactorily.
"I have come to the conclusion that in our district (Lilydale, a cool region) the optimum distance is 4 1/2 by 4 1/2 feet, practically 2,000 vines per acre, at least in the poorer soils; and, after careful observation, I am of opinion that vines planted any wider will not bear more fruit. This is, however, rather too close to be conveniently worked by horse labour. I should, therefore, recommend 5 by 5 feet. But on the Murray (a warm region) this distance would not suit at all, and I believe that the vine-growers are right to plant 8 by 8, and even 10 by 10 feet, in that district.
"In conclusion, I would advise every vine-grower starting in a new district to determine by experiment what is his optimum distance. He can make a pretty good guess from observations of soil and climate, and for the rest let him, instead of planting all his vineyard on one scale, plant different blocks at different distances apart, so that if he wishes to extend his vineyard later on he may know what is the most suitable way to do so. By a careful consideration of these and other points which regulate the growth and development of the vine, and a practical application of the deductions drawn from them, it is possible for the intelligent vigneron to obtain from his land a maximum of return with a minimum of labour, and also to regulate the strength of his wine so as to suit the requirements of trade, thus making viticulture one of the most remunerative as well as most attractive branches of agriculture."
In France, especially in the northern districts, the vines are placed much closer together than ever they are in Australia, and this means that only hand labour can be employed. But it has to be remembered that the scarcity of manual labour with us makes it necessary to arrange the vineyard with enough width between the plants for a horse. It is desirable, however, not to go to the other extreme and space the vines at too great a distance from each other; indeed, in favour of a closer planting, the following influencing circumstances should be borne in mind. In the elevated regions, where the rainfall is ample, the vines may be planted closer together than on the plains or on the lower slopes; firstly, because there is no fear as to a sufficiency of water; and secondly, for the reason that the vines, by being nearer together, protect one another from the inclement weather. Spring frosts also are very liable to occur in certain localities; and here again the vines, by being brought closer together, afford shelter to each other from the direct rays of the sun, which are particularly injurious when coming on top of a severe frost.
Then again, although some believe that in dry districts it is better to give each vine plenty of space, yet there are others who are of opinion that a closer formation is rather an advantage. And on this account: that since the roots come in contact with one another, they are compelled to strike deeper in search of water - just in the very place it is desirable they should go. In addition to the foregoing, it must not be forgotten that a dark-coloured soil absorbs more of the sun's heat than one of lighter colour; just as a dark coat is hotter to wear than a light-coloured one. For this reason, therefore, it is better for the plants to be closer together in a dark soil, since the shadow of the vines will then be over the root-producing areas.
In the South Australian Vinegrowers' Manual, which has been prepared by Mr. George Sutherland, under instructions from the Government of South Australia, the author expresses this conviction : That a very large proportion of the new vineyards of South Australia will be planted wide, especially in the warmer districts and on the lower rises of the foothills; but that after all 6 feet may be found the most suitable on more elevated localities, where we shall have to look for some of the best wines of the claret and hock type. One leading Californian authority, according to Mr. Sutherland, was a great advocate for wide planting. After an exhaustive inquiry into the matter, however, throughout the wine-producing countries of Europe, he became quite converted, and believed in closer planting. Mr. Francois de Castella also records the fact that in a block of vines at St. Hubert's (Lilydale, Victoria), every second vine was rooted out on one-half of the block. After ten years it was found that on the whole the closer vines had done better than those from which every alternate vine was rooted out.