ROCK AND JAPANESE GARDENS, WALL CREVICES 137 



To one who is in the beginning of this work of selecting plants for 

 rock garden use the impression should not be conveyed that every 

 plant which is dwarf in its habit of growth is desirable for the rock 

 garden. Many of these plants are extremely undesirable, such as 

 the creeping Jenny {lysimachia) and dead nettle {lamium maculatum), 

 mostly because of their tendency to grow rampant and to crowd out 

 and smother many of the more sensitive and more beautiful types of 

 rock garden plants. These plants are also difficult to eradicate from 

 the garden when once they become established. They should never 

 be used except in a rock garden on an extensive scale where the tend- 

 ency to spread will not eventually become offensive. In order to 

 maintain the true rock garden character it is very essential that plants 

 should be selected which are in harmony with the spirit of the garden. 

 Many so-called rock gardens are filled with the more common annuals, 

 with sweet williams, phlox, hollyhocks, and even large irises — plants 

 which belong to an entirely different type of garden, or which, because 

 of their size, are not in keeping with the scale of a minutely detailed rock 

 garden. 



It is not necessary, in the development of an interesting rock gar- 

 den, to use a large quantity of different types of plants. The success 

 of a rock garden is dependent largely upon the ability of the designer 

 to select proper types of plants for a specific purpose, whether the rock 

 garden be very small and occupying only a corner of the lawn, or 

 whether it be an extensive area in some wooded portion of the property. 

 Such plants as hydrangeas, spireas, petunias, and many plants of these 

 types which the reader has often seen in rock garden work, give evi- 

 dence immediately of the lack of knowledge of plants and of their 

 proper usage. 



It is true also that the plants which are used in rock gardens require 

 an amount of care in their maintenance equal to that given plants in 

 the more refined and formal types of garden work. 



For the person who has progressed along the path of successful rock 

 gardening it might be well to suggest that he should endeavour to 

 become intimately acquainted with the plants which he is using, 

 especially their source of origin and the conditions under which they 

 grew in their native locations. Plants which will withstand extreme 

 drought, hot suns, and extreme cold, if they are planted in the correct 

 locations in a rock garden, will not be hardy to any extent when planted 

 in the open border. In other words, such plants as the cheddar pink 



