ON SPEING-TENDERNESS IN PLANTS. 145 



had spent much time upon the Himalayan mountains, in tlie 

 district where the scarlet Rhododendron arboreum grew abun- 

 dantly. He assured me that in their native habitats, when occu- 

 pying warm southern slopes, they suffered much by the destruction 

 of their blossom buds from the late frosts, almost as much as the 

 early blooming kinds do in the gardens of this country, while, on 

 the contrary, where growing on northern aspects and experiencing 

 a greater intensity of frost they were uninjured. 



These are facts, exemplifications of which we can witness 

 every spring, in a more or less degree, in the gardens of this 

 country. 



Early flowering hardy plants are of no use as a general rule 

 in our gardens. Wet, winds, and frost will not associate with 

 bright and fragile corollas. The two are incongruous and in- 

 compatible. Plants which bloom in the open air before May 

 have little chance of expanding their flowers. But of blooming 

 plants I did not intend to take cognizance in this paper further 

 than as illustrative of the principle which I intended to elucidate, 

 though it will be obvious that they come into the category of 

 spring tender plants. To ornamental evergi'eens, such as Coni- 

 ferae, I intended these remarks especially to apply. 



An uniform temperature would be almost as injurious, though 

 in a different manner, to vegetable life as an excessively fluctu- 

 ating one. But so long as plants are not unduly excited, and 

 then as unduly retarded or checked, much damage will not 

 accrue. It is the alternate exciting by the influence of spring 

 suns and the antagonistic check by the frosts at night which pro- 

 duces the disastrous results, and renders plants spring-tender. 

 To counteract these injurious effects such hardy plants as are 

 known to be highly excitable should be planted in such a situa- 

 tion as will remove them as much as possible from the influences 

 which induce such excitability, for by removing or combating 

 the cause you of course prevent in an equal ratio the results. 

 Many plants are only spring-tender during the early years of 

 their growth, and when having reached four or five feet of altitude 

 evince no susceptibility to their influence. Abies cephalonica is 

 a remarkable instance of this. "Within a few days I have exa- 

 mined some of the earliest introduced plants, which for several 

 years after being planted scarcely progressed at all, being inva- 

 riably much damaged by spring frosts. The fact of their pro- 

 gressing very slowly is evident enough when the lower branches 

 are examined. They are now as luxuriant and as spring-hardy 

 as could be desired. 



The comparative hardiness of the same species in various 

 districts is apparently of a very anomalous character, and cannot 

 be explained otherwise than by attributing it to the influence of 



