The Manuring of Yineyards. 



1^3 



THE MANURING OF VINEYARDS. 



By J. C. Ross, Pli.I)., Kesearch Chemist, Elsenburg School of 

 Agriculture, and S. W. van Niekerk, Government Viticulturist. 



[The first part of this article appeared in last month's Jimninl. — Editor. 



Systems of Manuring. 



Keeping in mind the requirements of our vine fertilizer (approxi- 

 mately 85 lb. nitrogen, 120 to 130 lb. phosphoric oxide, and 90 lb. 

 potash per niorgen), we can make up a suitable mixture in many 

 dilt'erent ways. It must again be pointed out, however, that a 

 mixture of the above composition can hardly be expected to be the 

 best and most economical for all vineyards. For instance, there may 

 l)e cases where the amount of nitrogen should be reduced, as in the 

 case of vines which are found to make an exceptionally rank and 

 vigorous growth. Then the nitrogen might be reduced by one-half 

 or two-thirds for the first few years, and this will mean a great 

 reduction in the cost of manuring. It may also be found that the 

 quantity of potash used need not be so great. As stated before, the 

 only way to settle these points is by carrying out manurial trials in 

 the vineyards, as described later in this article. 



For a definite working basis we assume that tiie fertilizers men- 

 tioned have the following composition and prices: — 



* This is calculated as the approximate cost of production on the average faim, and 

 includes cost of cartage to the vinej^ard and spreading, at a liberal estimate. The manure is, 

 however, worth considerably more to the farmer. 



t This is the pre-war price. Very little obtainable during or since the war, and then at 

 a greatly increased price. 



J 'i'liis includes cost of the seed and the seeding, including one ploughing and one culti- 

 vation. Value of seed alone taken at 13s., 8U lb. per morgen. 



