212 STUDIES IN GARDENING 



the well-being of rock and mountain plants, the most 

 important are those of aspect. Of the more difficult 

 Alpine plants, many will thrive on one side of a stone 

 and not on the other, because of the difference of 

 aspect; and even to rock plants which are not difficult 

 aspect usually makes a great difference. It is, un- 

 fortunately, impossible to lay down hard and fast 

 rules about the aspects most suitable to particular 

 plants, because the general conditions of rock gardens 

 vary so much. Some are in warmer parts of the coun- 

 try than others. Some are fully exposed to the sun, 

 others shaded from it to some extent by the lie of the 

 ground or by trees or shrubs. Some are in gardens 

 with a north aspect, others in gardens with a south. 

 Thus a plant that would prefer a full south aspect 

 on a rock garden in a cold climate, might do best 

 with a south-west, or even north-west, aspect when 

 the rock garden was very hot and sunny. There is 

 much that the gardener can learn about his own rock 

 garden only by experience and observation; and 

 whatever general directions are given should be taken 

 as referring only to average conditions, and should 

 be modified where the conditions are not average. 

 But, if a rock garden is well placed and planned and 

 built, not too dry and not too damp, and in particular 

 not overshadowed by trees, there are certain direc- 

 tions about aspect that may be followed without 

 much fear. Thus a south-west or south-east aspect 

 is usually the best for the more delicate plants of the 

 higher Alps, and a full south aspect for those which 



