EOCK, ALPINE, FERN, AND WILD aAKDENING. 



5 



ivholly unnecessary, and generally injurious. The 

 mere fact of its being* utterly unnatural is strong- 

 presumptive evidence against its use, while ex- 

 perience shows that it does far more harm than 

 good. 



The rage for rough turfy loam, though light 

 in the main, is not seldom carried to extremes 

 in the cultivation of particular plants. For ex- 

 ample, in the cultivation of Alpines the necessity 

 for thorough drainage is so apparent that this 

 object is sought to be obtained through excessive 

 looseness and roughness of the soil; but any 

 one who has dug up an Alpine plant in its natural 

 habitat must have been struck with two features of 

 its root-run, its hardness and its fineness. The soil 

 is mostly the slow and gradual accretion of ages, 

 formed a few grains" or particles at a time ; and 

 timcj the great consolidator, compacts it into hard 



A 



masses. The porosity of the soil is maintained by 

 the addition of rocky debris or other matters — semi- 

 imperishable matter — to it. The same rule should 

 be observed in the artificial formation of root-runs 

 for rock plants. Fresh turfy loam should be laid 

 up for a year or more before use, as fresh vegetable 

 fibre can hardly be at once utilised by the roots. 

 It would also be benefited by one or more turn- 

 ings and by the addition of fifteen per cent, or so 

 of pure silica, or clean sharp silver sand, if not 

 sufficiently sandy ; five or so of leaf -mould, sweet 

 and well rotted, and from fifteen to twenty per cent, 

 of smashed stone. The latter is to be preferred to 

 crocks, potsherds, shells, or charcoal. The soil in 

 all cases should be on a layer or base of drainage 

 from two to six or more inches in depth. In cases 

 where plants are grown in pockets in rocks, it is 

 essential to success that these should either be bot- 

 tomless, or have one or more free outlets from their 

 lower sides or bottoms, for it cannot be too often re- 

 peated that stagnant water means disease or death to 

 all such plants. They cannot well have too much 

 water during the growing and flowering periods, if it 

 is kept in constant motion. This suggests a point of 

 great importance. In planting choice plants among 

 rocks, the latter must on no account be so tilted over 

 as to overhang the plants. The sun and the rain 



are essential to their life, vigour, and luxuriance, and 

 hence the importance of so placing the rocks as in 

 no way to interfere with those natural refreshers and 

 invigorate rs. Figs. 1, 2, and 3 give illustrations of 

 the different modes of placing rocks so as to avoid 

 the evils of overlapping, and get all the advantages 

 of a free sweep and full exposure to atmospheric in- 

 fluences. 



The proper disposal of rocks under the roots of 

 plants is of equal or more importance than their sky- 

 line. As a rule, all the pockets or artificial fissures 

 should cleave boldly doT\Tiwards rather than spread 

 out horizontally, and they should never on any 

 account run upwards, unless they have an opening 

 at the top into the external air (see Fig. 4, k, c). 

 But the best form of fissure is that shown at e, in 

 Fig. 4, while the worst is illustrated by a, in the 

 same figure, which may be described as a trap 



to kill plants, as no moisture can reach the roots 

 in such a crevice. Of course, between a and k 

 there may be a great variety of gradation, and 

 so long as the line of the fissure is sufficiently 

 downwards to convey moisture freely from to]) 

 to bottom, it may diverge widely from the vertical 

 line without injury to the j)lants. For example > 

 a crevice or fissure like c might answer almost 

 as well as e, for the successful culture of rock plants. 



Drainage and Water. — Assuming that the 

 major portion of the rockery — all its base, in fact 

 — is formed of soil, and that the top of the earth- 

 mound provides a dual surface, one of drainage from 

 four to six inches in depth, and the other of good 

 soil, such as that already described, a yard or so in 

 thickness : it is necessary for the outlet for the 

 drainage, where the base of the rockery is greatly 

 varied, to be at the lowest point. 



In Fig. 5, for example, the lower portions at 

 a, b, c would be converted into swamps, unless 

 outlets for the water were provided a.t the lowest 

 points of these rolling valleys or ravines. Unless 

 this were done, semi-aquatic plants would have 

 to be planted in such positions; but the combimi- 

 tion of a bog-fernery, and Alpinery in one is sel- 

 dom very effective. The one very proj)erly succeeds 



Fig. 4.- Crevices for Eock Plants. 



