320 THE GARDENER. [July 



in a subtratum of spongy peat, so as to retain moisture for the stony 

 matter that the cavity is to be filled with. As to soil, rock-plants are 

 found in all sorts ; but a good turfy loam, with plenty of silver sand 

 added, will be found to suit a greater number of kinds than any other. 

 The compost should be of a somewhat spongy character ; and if not 

 naturally so, it should be so made by the addition of well-decomposed 

 leaf-mould, cocoa-nut fibre, or, failing these, peat. If the trees of the 

 shrubbery are of a nature likely to send hungry roots into the mass of 

 good compost prepared for the rock-plants, it will be desirable to dig 

 a narrow drain to below the level of their roots, and fill it with con- 

 crete to the surface ; this will prevent the Alpine plants from being 



_ v^^&~3 



Rock-Garden on margin of Shrubbery. 



starved by their more vigorous neighbours. The kind of stone is not 

 an important point, and many people have to take their chance in this 

 respect, and use that which can be got. Millstone-grit and most kinds 

 of sandstone are good, where a selection can be made, but almost 

 any kind will do. Vitrified material should be avoided. 



" With the soil should be incorporated the smallest and least useful 

 stones and debris among those collected for the work, so that the 

 plants to be seated on the top may send down their roots through the 

 mixture of earth and stone, and revel in it. When this is well and 

 firmly done, the large stones may be placed — half in the earth as a 

 rule, and on their broadest side, so that the mass, when completed, 



