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, 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, &c.--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.