The Chemistry of Garden Crops 



fertilising constituents by the use of farmyard manure, &c., and have 

 more ' staple ' or substance given to them, while heavy, tenacious 

 clays are opened out, lightened, and rendered more amenable to 

 the influences of drainage, aeration, c., and so become less cold and 

 inactive. 



For the present purpose the principal garden crops may be 

 grouped in two classes, in accordance with their main characteristics 

 and the predominance of certain of their mineral elements. The 

 figures given below show the average percentage proportions of the 

 several minerals in the ashes of the different plants. 



In Class I. Phosphates and Potash predominate. This class 

 consists of the less succulent plants, and includes the following : 

 The Pea : containing, in 100 parts of the ashes, phosphates, thirty- 

 six ; potash, forty. Bean : phosphates, thirty ; potash, forty-four. 

 Potato (tubers only) : phosphates, nineteen ; potash, fifty-nine ; soda, 

 two ; lime, two ; sulphuric acid, six. Parsnip : phosphates, eighteen ; 

 potash, thirty-six ; lime, eleven ; salt, five. Carrot : phosphates, 

 twelve ; potash, thirty-six ; soda, thirteen ; sulphuric acid, six. 

 Jerusalem Artichoke : phosphates, sixteen ; potash, sixty-five. 



In Class II. Sulphur, Lime and Soda Salts are predominant. 

 This class consists of the more succulent plants, and includes the 

 following : Cabbage : containing, in 100 parts of the ashes, phos- 

 phates, sixteen ; potash, forty-eight ; soda, four ; lime, fifteen ; sul- 

 phuric acid, eight. Turnip : phosphates, thirteen ; potash, thirty-nine ; 

 soda, five; lime, ten ; sulphuric acid, fourteen. Beet : phosphates, four- 

 teen; potash, forty-nine; soda, nineteen; lime, six ; sulphuric acid, five. 



As a matter of course, Lentils and other kinds of pulse agree 

 more or less with Peas and Beans in the predominance of phosphates 

 and potash. So, again, all the Brassicas, whether Kales, Cauliflower, 

 or whatever else, agree nearly with the Cabbage in the prominent 

 presence of lime and sulphur ; ingredients which fully account for 

 the offensive odour of these vegetables when in a state of decay. 

 Fruits as a rule are highly charged with alkalies, and are rarely 

 deficient in phosphates ; moreover, stone-fruits require lime, for they 

 have to make bone as well as flesh when they produce a crop. As 

 regards the alkalies, plants appear capable of substituting soda for 

 potash under some circumstances, but it would not be prudent for 

 the cultivator to assume that the cheaper alkali might take the place 

 of the more costly one as a mineral agent, for Nature is stern and 

 constant in her ways, and it can hardly be supposed that a plant in 

 which potash normally predominates can attain to perfection in a 



