1 142 THE BOOK OF GARDENING. 



Drainage water, it has been found, will carry with it more or 

 less of the nitrate which has been applied to growing crops, but 

 it is a comparatively rare occurrence for water to pass through the 

 soil out of reach of plant roots, after the land is in condition to 

 work in the spring, in sufficient quantity to cause serious loss ; 

 besides, young plants take up nitrogen so rapidly, and send 

 their roots down so quickly into the soil, that the nitrate cannot 

 escape them, even if washed down by heavy showers or by 

 artificial waterings. 



Sulphate of Ammonia. — Next to nitrates the most available 

 form in which nitrogen can be furnished to plants is ammonia. 

 Sulphate of ammonia contains weight for weight more nitrogen 

 than nitrate of soda. When ammonia salts are applied to the 

 soil, the ammonia must be converted into nitric acid before the 

 plants can use it. If lime is deficient in the soil, the conversion 

 of ammonia into nitric acid will be retarded, and in this case 

 the ammonia, if applied to such crops as Onions, Beet, Potatoes, 

 &c, would at first be injurious rather than beneficial. On the 

 other hand, from an economical point of view, this manure cannot 

 be recommended for chalky and limestone soils, because lime 

 assists to expel the ammonia in a state of gas. Sulphate of 

 ammonia, however, has some peculiar advantages as a manure, 

 being slower in its action than nitrate of soda, and its efficiency 

 in the garden depends greatly on the completeness of the 

 accompanying mineral supply. It mixes well with bone-meal 

 or superphosphate. It is a capital fertiliser for Chrysanthemums, 

 foliage plants, Poinsettias, Potatoes, &c. For the colouring of 

 Grapes, sulphate of ammonia has been recommended, but it 

 must be applied in small quantities only. 



When nitrate of soda is used as manure, its nitrogen does not 

 enter into fixed combinations within the soil, but nitrate is dis- 

 solved in the soil-water, and unless taken ■ up by vegetation 

 much food material passes into the sub-soil beyond the reach of 

 the roots of growing crops. When ammonia salts are used, 

 part of the ammonia is temporarily taken up by the soil, but 

 it is more or less, according to the character of the soil and 

 of the season, converted into nitrates, and is then subject to 

 loss as when nitrate of soda is used. The loss will be less 

 if the manures are applied in the spring months, and to quickly- 

 growing crops. 



The gardener must remember that these concentrated nitro- 

 genous manures when used by themselves tend to produce 

 foliage rather than flowers or fruit, especially if the ground 

 has been partially exhausted of its mineral ingredients by 

 previous crops. To obviate this difficulty superphosphate of 

 lime, bone-meal, potash salts, and the like, may be given in 

 addition. 



