THE GROWING OF THE ORNAMENTAL PLANTS 233 
sheared evergreen. Sometimes the rocks are natural to the 
place and cannot well be removed; in this case the planning and 
planting should be such as to make them part of the picture. 
The real rock-garden, however, is a place in which to grow 
plants. The rocks are secondary. The rocks should not ap- 
pear to be placed for display. If one is making a collection of 
rocks, he is pursuing geology rather than gardening. 
Yet many of the so-called rock-gardens are mere heaps of 
stones, placed where it seems to be convenient to pile stones 
rather than where the stones may improve conditions for the 
growing of plants. 
‘The plants that will naturally grow in rock pockets are 
those requiring a continuous supply of root moisture and a cool 
atmosphere. To place a rockery on a sand bank in the burning 
sun is therefore entirely out of character. 
Rock-garden plants are those of cool woods, of bogs, and par- 
ticularly of high mountains and alpine regions. It is generally 
understood that a rock- garden is an as garden, although 
this is not necessarily so. 
In this country alpine-gardening is little known, largely be- 
cause of our hot dry summers and falls. But if one-has a rather 
cool exposure and an unfailing water supply, he may succeed 
fairly well with many of the alpines, or at least with the semi- 
alpines. Most of the alpines are low and often tufted plants, 
and bloom in a spring temperature. In our long hot seasons, 
the alpine-garden may be expected to be dormant during much 
of the summer, unless other rock-loving plants are colonized 
in it. Alpine plants are of many kinds. They are specially to 
be found in the genera arenaria, silene, diapensia, primula, 
saxifraga, arabis, aubrietia, veronica, campanula, gentiana. 
They comprise a good number of ferns and many little heaths. 
A good rock-garden of any kind does not have the stones piled 
merely on the surface; they are sunken well into the ground 
and are so placed that there are deep chambers or channels that 
