212 Journal op the Department of Agriculture. 



ELSENBURG. MULDERS VLEI. 



Furcliase of Fertilizers. — The present condition of the market for 

 fertilizers is still far from normal, and there exists considerable dis- 

 crepancy between the agricultural value and the commercial value of 

 many fertilizers. In the statement of the guarantee which accom- 

 panies any fertilizer frequentlj^ no mention is made of the quality 

 of the ingredients of the same kind in different fertilizers, so that 

 the farmer has often to pay top price for material that is very 

 ir soluble and slow in its action. Further, the purchaser should take 

 into account the state of fineness of the ingredients in those fertilizers 

 where the constituents are of a nature insoluble in water. In such 

 fertilizers as basic slag, bone meal, and bone dust the availability 

 of the phosphoric oxide increases with the fineness. 



At present the bulk of the fertilizers on the market are mixed or 

 compound, hence the importance of the statement of the quality of 

 the valuable constituents. For many reasons farmers have had to 

 fall back on these fertilizers, which supply in greater or less degree 

 most or all of the ingredients that the crop requires. The fault with 

 regard to most of these mixed fertilizers is that no attempt has been 

 made to compound a mixture suitable to the soil or crop. 



It is usually advisable that the farmer should purchase the 

 necessary ingredients and mix them himself or get a reliable fertilizer 

 merchant to compound the mixture according to his specification. 

 The farmer ought to know the manurial needs of his laud better than 

 the fertilizer merchant, and if he is not certain on the point, he can 

 get reliable information from the agricultural school in his area. It 

 is usually more economical for the farmer to mix his own fertilizers, 

 as there are often slack periods when the farm labour could be turned 

 to this work, thus saving the farmer the charges, sometimes very 

 heavy, that the merchant makes for mixing. 



In making up these mixed fertilizers, it is very necessary that 

 all the materials should be in a fine condition and possess as nearly 

 as possible the same degree of fineness. If heavy, finely ground 

 material is mixed with light, coarsely ground material by the 

 merchant, they may become almost entirely separated in transit to 

 the farm. This would give a fertilizer very uneven in composition 

 and consequently in its action on the crop, since all the coarse 

 material tends to work to the top of the bag and the fine stuff to the 

 bottom. 



If the farmer makes up his mixed fertilizers on the farm the 

 different materials should be thoroughly mixed in small quantities. 

 Any lumpy materials should be sifted before mixing and the mixed 

 material should be sifted and lumps broken up before bagging. 



In some commercial mixtures and in most mixtures that the 

 farmer would make up, superphosphate would be one of the 

 ingredients. This fertilizer can be mixed with bone dust, bone meal, 

 or guano and produce no serious loss unless the mixture is allowed to 

 lie for a long time, or the store is damp. This mixture on many of 

 our sour soils is preferable to superphosphate alone and a further 

 advantage is that it is easier to sow than superphosphate owing to its 

 drier condition. 



