Market-Garden Crops 291 



edible carrots, no less than 1000 pounds of a mixture 

 carrying 4 per cent of nitrogen, 4 per cent of phosphoric 

 acid and 12 per cent of potash should be used. In case 

 the season is favorable for rapid development, top-dressings 

 of nitrate of soda are very profitable. 



The other crops of this group, including celeriac, chicory, 

 horseradish, parsnip, radish and salsify, may be fertilized 

 with liberal applications of the basic fertilizer. It should 

 be remembered in connection with each that the crops of 

 this group require large quantities of potash, and that 

 phosphoric acid is relatively much less important. 



BULB CROPS 



This group includes chive, garlic, leek, shallot and 

 onion. Because the onion is the most important it is 

 discussed liberally. The fertilization of the other crops 

 may be the same. 



The growing of onions, either from seed or from sets, 

 and the growing of sets according to "intensive" systems 

 of practice, requires a soil of a suitable physical character 

 well supplied with all of the essential constituents of fer- 

 tility. The minerals should be supplied in abundance by 

 superphosphates and potash salts, while the nitrogen 

 should be supplied in the most active forms, and in even 

 larger amounts than for many other crops. The present 

 systems of growing these crops require that the sets shall 

 be planted and the seed sown more thickly than was 

 formerly believed to be desirable, which permits of a 

 larger yield to the unit of area, though it requires better 

 culture and a very much larger quantity of available plant- 

 food than was the case under the former rather "exten- 

 sive" systems of culture. Except in the case of very 



