ROCK, WALL AND BOG GARDENS. 



be it stone or brick, which are already most artistic, and need only the addition of a 

 few homely wall plants, such as stonecrop, roof flax, London pride, antirrhinum, wall- 

 flower, fumitory and roof leek to make them doubly so, especially if some of the 

 large free-growing cabbage roses can be trained over the coping. Such simple, old- 

 fashioned flowers seem to harmonize better with old walls which do not form a part of 

 the main gardens far better than the newer varieties ; but, even with them, care should 

 be taken not to overdo it, as old, weather-stained walls are beautiful in themselves, and 

 should not be so fully planted up as to hide their weather-beaten surfaces. Nor should 

 too many varieties be used. Old black slate walls in the English Lake District, which 

 are so beautiful as to attract the attention of -every visitor who sees them, usually only 

 boast two varieties of simple fern, and two or three of moss, and yet provide an object 

 lesson in the effectiveness of the simplest treatment, Nature pointing a way for us to 

 follow in our wall planting. 



Where a brick or stone wall is being built specially for use as a wall garden, mortar 

 made with sand, not ashes, should be used and, of course, if there is any suspicion that 

 the sand is salt, it should be washed. To slope back the face of an independent wall 

 sufficiently to encourage the rain to soak in between the joints, as in building a retaining 

 wall, is not usually possible, and in this case the best way is to have projecting courses, 

 as shown in the accompanying sketch (111. No. 272). Where the coping is above the 

 eye from every point of view so that its upper surface cannot be seen, holes may be 

 made in it as shown in illustration No. 271, so that they may be filled with soil and 

 a larger range of plants may be placed there where their trailing branches will hang 

 over the wall. 



Where the area of a garden is so restricted that it is impossible to devote any 



part of it exclusively to rock plants, these 

 may still be grown very effectively by 

 arranging a boulder- built edging to retain 

 the piled up earth on an herbaceous border. 

 Not only does the raising of the border 

 give the flowers it contains more prominence 

 but it will tend to keep the plants growing 

 in the fissures between the boulders moist 

 and so a double advantage is gained. 



Illustration No. 270 shows how this 

 may be done. As there can obviously be 

 no attempt at imitating natural rock, it 

 is built in two regular tiers, and in order 

 to prevent an appearance of a flight of 

 steps or a monotonous row of stones, large 

 " throughs " are introduced which also give 



FIG. 270. 



shelter to small and tender plants. 

 What to I n deciding what to plant in our rock or wall gardens, we are confronted with un 



plant. embarras de choix, for there is an enormous range of material upon which to draw. 



The best way is for the beginner to start with a few of the common sorts which will 

 succeed well, and then take note of and add others as he comes across them if they 

 appeal to him and appear suitable to the position they are to occupy. Preference 

 should always be given to native varieties, and no better advice could be given than to 

 stroll through pastoral country and note the common harts-tongue fern for a moist 

 position, the three main varieties of tree fern for shade, the tall foxglove, the honey- 

 suckle, of which two kinds will be noticed, the harebell, the parsley fern, and many 

 others which thrive on walls and rocks, and use these in positions as like those in 

 which they are found in nature as possible. 



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