PART L] CULTURAL 



SOIL. 



The great majority of alpine plants thrive best in deep, cool, 

 and gritty soil. In it they can root deeply, and when once they 

 are so rooted, they will not suffer from drought, from which they 

 would quickly perish if planted in the usual way. Two feet 

 deep is not too much for most species in dry districts, and it is 

 in nearly all cases a good plan to have plenty of broken sand- 

 stone or grit mixed with the soil. Any good free loam, with 

 plenty of sand and grit, will be found to suit many alpine plants, 

 from Pinks to Gromwells. But peat is required by some, as, 

 for example, various small and brilliant rock-plants like 

 Menziesia, Trillium, Cypripedium, Spigelia inarilandica, and 

 other mountain and bog plants. Hence, though the general 

 mass of a rock garden may be of an open loam nature, it will be 

 desirable to have a few masses of sandy and leaf soil and peat 

 here and there. This is better than forming all the ground of 

 good loam, and then digging holes in it for the reception of 

 small masses of peat. The soil of one or more portions might 

 also be chalky or calcareous, for the sake of plants that are 

 known to thrive best on these formations, as Polygala calcarea, 

 the Bee orchis, and Ehododendron chamsecistus. Any other 

 varieties of soil required by individual kinds can be given as 

 they are planted. 



Much consideration has been given by botanists to the 

 plants that grow on the different formations, but we have 

 evidence in British gardens that the good soils common in them 

 will sustain in health a great number of kinds well, that in 

 Nature are found on soils of a special character. 



Mr Correvon, who has given much thought to the matter, 

 writes as follows in The Garden: 



The flora of the Alps depends in a much greater degree than 

 that of the plains on the chemical nature of the soil. We know 

 that from the point of view of chemistry, the mountains are divided 

 into two main classes, namely, the calcareous and the granitic, 

 otherwise the sedimentary and the igneous. 



All the mountain ranges of the Alps are either of limestone or 



