THE BEST STONES AND SOIL. 85 



edge. Thickish stones with a flat base are the most 

 suitable for this purpose. 



In the body of the rockery it should be a cardinal 

 point to set the stones in such a way that rain can 

 find free admission between them. 



Those who have rock walls, which potentially present 

 the driest conditions under which Alpines are likely 

 to live, are pleasantly surprised at the vigour of many 

 of their plants, and there can be no doubt that plants 

 which are able to send their roots well back into the 

 soil of a bank are capable of getting along with very 

 Httle help from rain, most of which flies off from the 

 face of the stones. Where, however, the plants have 

 no such extensive root run they wiU be helped by all 

 the rain they can get in summer. In winter some of 

 them would get too much if glass was not fixed over 

 them to throw it off. 



Some Alpines will grow in anything — ^nay, they 

 will grow in a crack or crevice in a large stone, or on 

 its face where there is no soil at all, but others are not 

 equally accommodating, and in view of the fact that 

 practically every species is the better for good soil it 

 is worth while to consider whether the natural soil of 

 the garden, should it be available, is good enough. 

 When a considerable body of soil is wanted for a rock 

 garden it can only be drawn from the garden by 

 reducing the general level or making a hollow. Given 

 a fairly large kitchen garden, the soil of which has 

 been trenched and manured, thus raising its level 

 considerably, a few cartloads could perhaps be with- 

 drawn without spoiling the subsequent crops. 



