Another distinctive style in rock gardening is the Japanese garden. This is a wide subject, and one that, to the Japanese gardener, is worthy of a lifetime of concentrated study. The chief difference between a Japanese garden and a European garden is this. In our gardens, we plant either for a landscape picture, to a formal pattern, in order to complete our collection of horticultural specimens, or to produce perfectly grown plants for exhibition. The Japanese design their gardens symbolically, and every stone set inin a Japanese rock garden must have its meaning, and must be chosen for the suitability of its size and shape, and set in just the right position for that kind of stone. A Japanese gardener searches perhaps for years for a stone of exactly the right proportions and outline. We, however, merely search for stones that satisfy a need for something more or less picturesque, and then leave it at that.
It is impossible to go fully into this subject in a limited space; but as an illustration, let me explain that in the conventional Japanese garden you would always find three stones (or three plants, for there might be the same idea worked out in other materials). representing God (or the Guardian), Man (or Worship), and Earth (or material things). There would also be stones or other material of secondary importance, but still full of meaning, each with its name and place in the scheme. There might be many more such items, but each and every item must be known, named, and valued in the layout of the garden.
It is an interesting subject to study, for any gardener with time to devote to it. Since the size of a Japanese garden can be anything from 6 in. to many acres, this is an ideal phase of gardening for the owner of a tiny plot. There are a number of good books on the subject in most libraries, and any who care to tackle the task of making a Japanese garden are advised to read these.
A new rock garden is best left for a few weeks after construction, before planting is begun, so that the soil and rocks can settle well. Although the utmost care is taken to ram soil well into all crevices as the building proceeds, so that no large air spaces are left in which plantcan become starved and dry, a certain amount of settlement or movement is inevitable, and it is best that this should take place before there are any plants to be disturbed in the process.
Rock plants are usually bought in, or just tipped from , and they should be set out in the prepared soil pockets with as little disturbance as possible. In the case of home-raised , set out from boxes, the planting process is similar to that of ordinary bedding out. Care must be taken not to damage the tender necks of small plants, but all plants must be set firmly, and have the soil well pressed down over the .
Rock plants like a cool, moist-run; they rapidly die off if the soil surrounding them cakes and dries. Until the plants themselves are large enough to cover the soil surface of the whole pocket, small granite or limestone chippings, or pea gravel, can with advantage be used as a cover to the surrounding soil. These prevent much surface evaporation, and do not interfere with the normal development of roots and foliage.