COMMERCIAL FERTILIZERS 69 



out knowing- the source of the various materials .which 

 enter into the composition of the brands used. 



114. The home mixing of fertilizers. Home mixing of 

 fertilizers is increasing in popularity. The following ad- 

 vantages may be mentioned : ( i ) The grower knows ex- 

 actly the kind and amount of each ingredient used; (2) 

 he can adapt the mixture to the needs of the different 

 classes of crops to be grown; (3) he can adapt the mix- 

 ture to the needs of the particular soil to be cropped ; (4) 



FIG. 14. LIME SPREADER 



he usually saves several dollars a ton; (5) he becomes 

 more intelligent every year in the application of the prin- 

 ciples relating to plant nutrition. 



Numerous experiments have proved that home-mixed 

 fertilizers are fully as valuable as factory-mixed goods 

 of equivalent composition. 



The arithmetic of home mixing is very simple. Sup- 

 pose fertilizer is wanted that will contain 4 per cent of 

 nitrogen, 8 per cent of phosphoric acid and 10 per cent of 



