PART L] CULTURAL 69 



evaporation are no doubt important factors in the growth of 

 plants, but it would be waste of time to dwell upon the endless 

 particulars which make it impossible that the conditions which 

 prevail on the Alps can be imitated in the valley of the Thames. 



" The first necessity for growing choice alpines is to secure 

 perfect drainage for the soil in which they grow. This may 

 seem strange to those who have seen them growing on the 

 mountains, often apparently in perpetual wet; but there the 

 soil is never water-logged, or charged with stagnant moisture, 

 but the wet is always in rapid motion and changing. Suppos- 

 ing that no part of a garden naturally gives the conditions in 

 which alpines will thrive, we must make these conditions by 

 artificial means. Those who wish to grow them on flat borders 

 or retentive wet soils may do so on the ground-level by 

 digging out the soil to a depth of 3 feet, and draining the 

 bottom of the bed to the nearest outfall, and filling up to the 

 surface with soil mixed with two-thirds of broken stone, either 

 in small or large pieces. But in heavy soils, where large stones 

 are easily obtained, still better beds for alpines may be made by 

 enclosing the space with large blocks to a height of 2 feet or 3 

 feet, and filling up as before directed. The sides of these stone 

 blocks can be covered with many ornamental plants in addition 

 to those which are grown on the raised surface. But the 

 commonest way of cultivating alpines is upon what are called 

 rockeries, or loose rough stones laid together in different forms 

 and methods. 



" The forms in which the rockery, usually so called, can be 

 constructed may be divided into three : (1) The barrow-shaped 

 rockery, (2) the facing rockery, and (3) the sunk rockery. The 

 first may be raised anywhere; the other two depend partly 

 upon the configuration of the ground. No wood or tree roots 

 should be used to supplement any of them ; they must be all 

 stone. The kind of stone is seldom a matter of choice ; every- 

 one will use what is most handy. The rougher and more 

 unshapely the blocks the better. The size should vary from 40 

 or 50 Ibs. to 3 or 4 cwts. No mortar or cement for fixing them 

 together must ever be employed ; they must be firmly wedged 



