inches deep to receive the fertilizers and seed. Care should 

 also be taken to mix the fertilizer with the soil in the furrow 

 before the seed is planted. 



Kinds of Fertilizers and Methods of Application. 



The results of repeated and long-continued experiments have 

 shown conclusively that the fertilizer should be compounded 

 with reference to the needs of the potato crop. On all our New 

 England soils, and Massachusetts is nb exception, it is necessary 

 to practice liberal fertilization. 



The general practice is to grow the potato crop exclusively 

 with the aid of commercial fertilizers, and to use the farm-yard 

 manure for the preceding crop of corn. 



A well-balanced potato fertilizer should contain all three of 

 the essential ingredients: nitrogen, phosphoric acid and potash. 

 The nitrogen should be supplied in nitrates, ammonium salts 

 and organic materials because the aim should be to have a 

 constant supply present in readily available form for the use 

 of the plant during its entire growing period. Furthermore, if 

 it is applied in several forms there is less danger of loss by 

 leaching. The phosphoric acid content must be relatively high, 

 because its function is to supply not only the needs of the 

 growing plant but also to hasten maturity or the ripening of the 

 crop. The percentage of potash should also be high, not only 

 because the crop of tubers removes a large amount of it but 

 because it is necessary in large quantities for building up the 

 vines, and especially in the leaves, to assist in the formation of 

 the starch, which is later deposited in the growing tubers. 



The high-grade sulphate of potash is sometimes used because 

 of its supposed beneficial influence on the cooking quality of 

 the crop. In a dry season, however, the muriate of potash 

 may give a larger crop; hence many successful growers prefer 

 that at least a part of the potash be present as muriate. 



The proportions of the different elements in a ton of fertilizer 

 should be about as follows: — 



Per Cent. 



Xitrogcn, 83 to 4 



Phosphoric acid, * . . 8 to 10 



Potash, 7 to 10 



