52 STUDIES IN GARDENING 



period, and where it can throw out its tufts in all direc- 

 tions. If it is grown on a slope in England (or Amer- 

 ica), however, it is difiScult to protect from drought, 

 especially as it needs all the sun it can get. It is best 

 grown, therefore, in a little hollow of the rock garden, 

 which will catch all the rain that falls into it, and 

 where the plant will have plenty of room for increase. 

 Gentiana vema is not difficult to grow when once its 

 needs are understood, because it is not very impatient 

 of moisture in the winter. There must be good drain- 

 age below it; but, if such drainage exists, it can and 

 should be grown in rich soil — a mixture of turfy 

 loam and leaf -mould, for instance, suits it well. 



But there are other plants which need as much 

 moisture in the summer, but which are so impatient 

 of damp in the winter that they must be provided 

 with a much lighter and poorer soil. It is plants such 

 as these that are particularly difficult to grow; and 

 yet a good many of them can be grown successfully 

 if only the rocks are arranged so as to protect them 

 both from drought in the summer and from damp in 

 the winter. Like Gentiana vema, they must be grown 

 in little hollows among the rocks, but in hollows where 

 the drainage is very sharp. The pockets in which 

 they are planted should not themselves be sloping, 

 but slightly depressed in the middle like a saucer, so 

 as to catch the rain. They should be planted close 

 to a rock arranged so that their roots can run under 

 it and be kept cool by it, but the other rocks should 

 come closer together downwards like the sides of a 



