Properties of Potash 



away the chlomre of magnesia (which is very 

 soluble by the way) before the seeds begin to 

 germinate. 



Kainite should never be given as a top dressing 

 to a growing crop or it will kill a great part of it. 



Potash can be used as a top dressing for pasture 

 land and clover in February at the latest, and for 

 preference in January ; and should never be applied 

 after the first cutting of clover. 



Properties of Potash. 



Potash salts, especially the chlorure, are very 

 soluble in water, but in spite of this no loss need be 

 anticipated as long as there is limestone in the soil, 

 because potash is very quickly rendered indissoluble 

 and fixed on the humates. In fact, experiments 

 made at Rothamstead show that they sink very little 

 below the surface. In these trials nearly the whole 

 quantity could be located within ten inches of the 

 surface, despite the fact that the ploughings of many 

 years had evidently mixed the soil very thoroughly. 

 That is why it is advisible to harrow in potassic 

 manures well, so as to ensure some part penetrating 

 to a fair depth instead of letting it all remain near 

 the surface. 



If an application of kainite is followed by a suffi- 

 ciently prolonged period of dry weather it may 

 happen that the potash, and more particularly the 

 chlorure of magnesia, absorbing all the moisture in 

 the soil, will form concentrated solutions which are 

 extremely corrosive and destructive to plants. This 

 will affect pasture, wheat, etc., equally. When 

 applying potash to soils that are poor in limestone 



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