FERTILIZERS FOR GRAPES 



101 



Table II. — Average Increase in Grape Yields and Average 

 Financial Gain from Fertilizer Applications 



N = nitrogen, P = phosphorus, K = potassium, Ca = lime. 

 Gains in tons per acre. 



From this last table the benefit from nitrogen appears quite 

 evident since every combination in which it appears gives a 

 substantial gain over the one from which it is absent. Phos- 

 phorus and potassium without the nitrogen, lead to only a 

 slight increase over the check ; and lime appears to be of no 

 benefit. Financially, the complete fertilizer and lime com 

 bination, the nitrogen and phosphorus combination and the 

 phosphorus and potassium combination failed to pay their cost 

 in five of the ten comparisons ; the complete fertilizer was used 

 at a loss four times out of ten ; and the nitrogen and potas- 

 sium combination three times out of ten. Lime had no 

 appreciable effect on either vines or fruit. 



" Xo eft'ect of the fertilizers on the fruit itself, aside from 

 yield, was shown for the first three years ; but in 1912, and even 

 more markedly in 1913, the fruit from the plats on which 

 nitrogen had been used was superior in compactness of cluster, 

 size of cluster and size of berry. In 1912 also, when early ripen- 

 ing was a decided advantage, the fruit on the nitrogen plats 

 matured earlier than that on the check plats. In 1913 the 



