72 GARDEN PLANNING 



ground. In "full-trenching" the process has 

 the effect of reversing the relative positions 

 of the upper and lower layers of soil, so that 

 that which was situated, say, two feet below 

 the surface comes to the top, and the top layer 

 goes to the lower level. 



So complete a reversal may be admirable 

 treatment for ground which has long been in 

 tillage, and therefore already broken up to 

 the trenching depth, but it would be inad- 

 visable in the case of new ground such as we 

 are considering, the subsoil of which had 

 not seen the light perhaps for centuries. On 

 such ground the subsoil would be compacted 

 and wanting entirely in the constituents 

 which furnish food for plants. It is clear, 

 therefore, that if full-trenching were adopted 

 the gardener would have a very poor surface 

 layer in which to grow his flowers. 



A better plan would be to "half-trench," 

 which consists in removing the surface soil 

 in sections, then breaking up the subsoil with 

 a fork, and subsequently replacing the surface 

 soil. But there is still a better method for 

 the garden maker, designed to effect the more 

 or less complete mixing of the soil and subsoil 



