416 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



In preparing the ground it is advisable to dig it very deeply, 

 or better still to trench it, and thus both avoid stagnant moisture 

 in the winter, and save the plants from suffering from drought in 

 the summer. Moreover, since some alpines are very deep-rooting, 

 trenched soil offers a further advantage to them. Different varieties of 

 soil require different treatment. If plants are to do well in heavy 

 soil, it will require plenty of drainage. If a rock garden is to be 

 made on the flat it would be quite an easy undertaking if it is possible to 

 get a good quantity of road scrapings, not from tarred roads. If the 

 scrapings are mixed with plenty of leaves and garden soil, a good 

 gritty compost suitable for alpines is obtained. A well-decayed 

 garden refuse heap is also a useful compost for the rock garden, and 

 plants thrive well in it. It is not advisable to add limestone or 

 mortar rubble to the soil, as there are many alpines which are not 

 at home in soil containing lime. Hence it is best to add the limestone 

 or mortar rubble when planting such plants as require lime. It is 

 best to make mounds on the large rather than on the small scale, as by 

 so doing the plants do not suffer from drought as they do on a small 

 mound if not kept well watered during the summer months. 



A plan must be drawn, or an idea formed as to paths, water, &c, 

 and straight paths or anything that would cause the rock garden to 

 look formal should be avoided. The charm of the garden lies in the 

 many little surprise corners, and nooks in which the most interesting 

 plants will be found nestling. Moreover, winding paths give many 

 different aspects, which are very necessary for the different plants. 

 They provide shady nooks, and nooks in half shade, as well as others in 

 full sun. This variety of aspect is most important for the successful 

 growing of the many and various rare alpines. 



When building a rockery the stone should be placed in as natural 

 a manner as possible. Start from the bottom and build upwards, 

 fixing the stones firmly, so that the gardener may stand on them when 

 weeding. The stones should always be laid the way of the grain and 

 tilting slightly inwards, so that the rain may run back to the roots 

 instead of dripping over and spoiling the plants below. Give promi- 

 nence to the boldest part of the rock stone ; avoid squareness ; and use 

 the thinner flat stones for paths, stepping-stones, &c. It is very impor- 

 tant to take care to fill up well behind each stone and also under it, as it 

 is laid in position. Make all quite firm, for if this is not done the result 

 will be that after heavy storms either the stone or the soil will sink, and 

 by so doing cause a great deal of mischief. The plants undermined 

 will suffer from drought, and the hollowed-out soil will harbour rats, 

 mice, slugs, and harmful insects. 



Having thus built the rockery, we will first plant it with some of 

 the many small shrubs which are suitable. It is much easier to 

 plant alpines to shrubs than to plant shrubs to alpines, and therefore 

 the shrubs should be planted first. There is a large variety of shrubs 

 from which a good choice may be made, and the following are especially 

 suitable for a small rock garden : — the dwarf varieties of Picea excelsa> 



