THE ROTATION OF CROPS 



IN THE 



VEGETABLE GARDEN 



THIS is a subject worthy the attention of those who aim at the 

 largest possible production and the highest possible quality of 

 every kind of kitchen-garden crop, for it concerns the natural rela- 

 tions of the plant and the soil as to their several chemical constituents. 

 The principle may be illustrated by considering the demands of two 

 of the most common kitchen-garden crops. If we submit a Cabbage 

 to the destructive agency of fire, and analyse the ashes that remain, 

 we shall find in them, in round numbers, eight per cent, of sulphuric 

 acid, sixteen per cent, of phosphoric acid, four per cent, of soda, 

 forty-eight per cent, of potash, and fifteen per cent, of lime. It is 

 evident that we cannot expect to grow a Cabbage on a soil which is 

 destitute of these ingredients, to say nothing of others. The ob- 

 noxious odour of sulphur emitted by decaying Cabbages might indi- 

 cate, to anyone accustomed to reflect on ordinary occurrences, that 

 sulphur is an important constituent of Cabbage. If we submit a 

 Potato tuber to a similar process, the result will be to find in the 

 ashes fifty-nine per cent, of potash, two per cent, of soda, six per 

 cent, of sulphuric acid, nineteen per cent, of phosphoric acid, and two 

 per cent, of lime. The lesson for the cultivator is, that to prepare a 

 soil for Cabbage it is of the utmost importance to employ a manure 

 containing sulphates, phosphates, and potash salts in considerable 

 quantity ; as for the lime, that can be supplied separately, but the 

 Cabbage must have it. On the other hand, to prepare a soil for 

 Potatoes it is necessary to employ a manure strongly charged with 

 salts of potash and phosphates, but it need not be highly charged 

 with soda or lime, for we find but a small proportion of these 

 ingredients in the Potato. There are soils so naturally rich in all 



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