36 



Potato Growing. 



[APRIL, 



3 to 4 cwt. of superphosphate and i cwt. of sulphate of potash 

 or its equivalent per acre. Where no dung is available the 

 quantities of artificial manures should be increased to 2 cwt. of 

 sulphate of ammonia, 6 cwt. of superphosphate and 2 cwt. 

 of sulphate or muriate of potash. Manures should not be used 

 in greater quantities than those included unless it is known to 

 be profitable to do so. 



3. With regard to planting, it is important that the first 

 sprouts should suffer no damage. This can be obviated by 

 boxing and careful handling ; but if boxing is impracticable 

 the aim should be to let the plants form their first sprouts in 

 the soil. In early planting there is practically no danger from 

 frost. As long as the soil is cold the tubers make less progress 

 than they would do in boxes, and on light or lumpy soils in a 

 dry climate early planting largely obviates the risk of drought. 



Leaf Curl of Potatoes. — Although from 10 to 14 tons of 

 potatoes per acre is no uncommon crop in various parts of the 

 country, the average return is only six. To some extent this 

 wide variation is due to climatic and manurial influences, but 

 in many cases light crops are due to the use of inferior seed. 



For the grower who makes use of obviously diseased and 

 blemished seed there is no excuse, but it is unfortunately 

 impossible to detect seed affected by the disease known as 

 " Potato Curl Leaf," one of the " deterioration " potato 

 diseases which can seriously reduce the crop. This complaint 

 is more common in the drier and warmer parts of the country 

 and is specially prevalent where mature seed, obtained from 

 fully-ripened plants, is used. 



As the disease is hereditary, it is of the utmost importance 

 to avoid sowing seed from dwarfed plants or even from 

 healthy-looking plants in plots or fields in which the potato 

 leaf curl is common. 



Where immature potatoes are used for seed each year, the 

 disease is very rare. Growers will find that the planting of 

 good seed potatoes, obtained from the more northerly parts of 

 the country, will constitute the best insurance against the 

 occurrence of Leaf Curl in their crops. 



Further information regarding Potato Leaf Curl is given in 

 the Ministry's Leaflet No. 164. 



