1920.] 



Potash Fertilisers. 



4i 



seen. Sulphate and muriate of potash may, for practical 

 purposes, be regarded as equal in potash content : — 



Manure and Potash 

 Content per cent. 



Kainit (14). 



Muriate 

 Potash Salts and Sulphate 

 (30). of Potash 

 (say 50). 



Potash Salts (30) 

 Muriate of Potash j . . 

 Sulphate of Potash | 15°J 



lb. 

 112 



52 



32 



lb. lb. 

 240 400 

 112 187 



67 112 



SUGGESTIONS FOR APPLICATION OF POTASH TO CROPS. 



Potatoes. — Shortage of potash is probably felt more severely 

 in the case of potatoes than of any other farm crop. The light 

 loams, the gravels and sands on which potato growing has 

 developed so much in recent years are typically poor in potash. 

 Growers, therefore, should endeavour to apply potash in one 

 or other of the forms already mentioned. 



* Usual Application = 1 to 2 cwt. sulphate of potash, or 



185-370 lb. 30 per cent, potash salts. 



Mangolds,— Mangolds respond well to dressings of salt, and 

 there is reason to believe that for a season or two salt can 

 replace most of the potash usually given, especially when the 

 normal quantities of farmyard manure are applied. The time 

 seems now ripe, however, for testing the effect of a little 

 potash in addition, particularly on the lighter classes of soil. 

 *Usual Application = 3 to 6 cwt. kainit, or 156 to 312 lb. 

 30 per cent, potash salts, or 96 to 192 lb. sulphate or 

 muriate of potash. 

 Turnip* and other Green Crops. — 



* Usual Application = 2 to 4 cwt. kainit, or 104 to 20S lb. 



30 per cent, potash salts, or 64 to 128 lb. sulphate or 

 muriate of potash. 



Cereals. — Generally speaking, potash manure is not much 

 required by cereals. Wherever land is known to benefit from 

 potash fertilisers — usually light land and peaty soils — a dressing 

 may well be tried. 



Usual Application = 2 cwt. kainit, or 104 lb. 30 per cent, 

 potash salts. 



* Where an average dressing of dung is given, the smaller quantities of 

 the manures mentioned should be used. 



