ASPARAGUS 23 



to root crops. (But, against this practice, see under 

 Cultivation for Rust.) 



(3) Chemical fertilizers should always supplement 

 manure, in the proportion per ton as given under Pre- 

 paring the Permanent Bed. But 



Chemicals may be used without manure, mixed in the 

 formula 4 per^ cent nitrogen, 8 per cent phosphoric acid, 

 10 per cent potash, 1,000 to 1,500 pounds per acre. 

 Apply this before setting, and each spring, with an 

 additional top-dressing, after the cutting season, per 

 acre at least 250 pounds nitrate of soda, 300 of super- 

 phosphates, and the equivalent of 100 pounds of actual 

 potash. (Voorhees.) Other formulae give a larger per 

 cent of potash. A good spring dressing consists of 450 

 pounds Peruvian (Chincha) guano and 400 pounds 

 muriate of potash per acre. 



Nitrogen applied in April will benefit the season's 

 crop if there is sufficient rain to carry the food to the 

 roots. But it is probable that nitrogen is best dis- 

 tributed through the year, either as nitrate of soda 

 or as liquid manure. 



Manure versus chemicals is summarized in Farmers' 

 Bulletin No. 233 ; " If the land is in good condition a 

 well-balanced commercial fertilizer may produce as good 

 yields as manure and be cheaper." Notice the if; 

 manure helps to keep the land in good condition. 



Common salt, frequently advocated, is never to be 

 used on clay soils, and in general its value is not proven, 



