ARTIFICIAL MANURES AND HORTICULTURAL PRACTICE. 61 



by a suitable addition of concentrated commercial fertilisers, for 

 the purpose of rendering the former more rapidly available in 

 order to force particular garden products " out of season," should 

 commend itself to the horticulturist on account of the directness 

 with which he can thus reach the object in view. Both good 

 economy and the preference for a healthy and vigorous condition 

 of our cultivated plants advise a change from an indifferent 

 system of manuring to one of a more rational character. 



Curiously enough the ready availability of the best and most 

 concentrated artificial fertilisers is sometimes used as an argu- 

 ment against their use, as compared with slower or more lasting 

 manures. If a manure lasts, it simply means that the return for 

 its cost is delayed, the capital it represents yielding no interest 

 until it is realised. I would emphasise the fact that a well-chosen 

 artificial manure should act promptly and decisively upon 

 the crop, or upon the particular plant to which it may be 

 applied. 



It is hoped that the facts now laid before you will assign to 

 artificial manures their proper place in the garden, the conserva- 

 tory, and the orchard, and will direct the attention of the 

 horticulturist and the orchardist to the great value of these 

 concentrated fertilisers, which have hitherto been overlooked or 

 but insufficiently appreciated. 



Discussion. 



Mr. A. D. Hall, Principal of the South Eastern Agricultural 

 College, suggested that the lecturer, and still more so, many of 

 the gardening papers, laid far too much stress on the composition 

 of particular plants as a guide to their manurial treatment. It 

 was Liebig's initial theory that it was only necessary to put into 

 the soil the ash constituents (and nitrogen) taken out by each 

 crop, but experimental evidence and practical experience had 

 shown not only that this view was incorrect, but that in many 

 cases the very constituent that was least in amount in the 

 plant's composition was the one upon which its growth mainly 

 depended under ordinary conditions of cropping. To give 

 some examples from the Rothamsted figures ; swedes are 

 usually grown with superphosphate or other phosphatic manure 

 alone, yet a crop of swedes removes only 22 lbs. of phosphoric 



