THE FLORIST'S JOURNAL. 
4 0 
with long seasons of drought, there is evaporation from the surface 
of plants, as well as in countries of the opposite character ; but in 
the latter, there is evaporation all the year’round, which keeps the 
plants at a comparatively low temperature ; so that where heavy 
rains fall upon them for a period of considerable length, while the 
temperature is at the same time sinking, from the natural course 
of the season, the evaporation is greater, in proportion to the tem¬ 
perature, than in countries of tropical character. The result of 
this is, that when the temperature sinks, the depositation of water 
upon the plants, the evaporation, and the consequent cold, are all 
increased to a degree which chills the plants, to the serious injury 
of their health and growth, and still more of their flowering, if 
the rain, and consequent cold, come on when the plants are in 
progress to their floral development. 
In summer, this change is never so great, nor is the heat sunk 
so low as to do serious injury to the hardy plants which grow and 
flower out of doors ; and the tender exotics are, at the same time, 
safe in their greenhouses and stoves ; so that during the summer 
there is very little to hurt either the growth or the bloom of any 
sort of flowers, except it be the difference of temperature between 
the day and the night; and though this be great, and the morning 
dew have abundant matter though it may not form abundantly, 
the radiation of heat from the ground, and the warm state of the 
surface of the plants, combines in preventing any serious injury. 
So also in winter, rain does no serious injury, except by washing 
some of the plants out of the ground, by occasioning floods, or, 
when it is accompanied by too high a temperature, starting the 
plants into a premature vegetation. The last of these is the most 
serious, especially if it occurs in the latter- part of the winter, or 
in the spring ; and in the last of these it is peculiarly injurious, 
because it is apt to bring on frost, or even to chill the young 
vegetation more than a moderate frost would do. 
Thus, though there is no very great danger to vegetation, 
during the confirmed part either of the summer or of the winter— 
there being few or no out-door flowers at the latter season, there 
is great danger throughout the whole spring, which may be 
regarded as a blending together of the winter and summer. Still, 
however, this is only casual, in the very worst years; and in the 
favourable ones, which in this respect are the great majority, it 
does not occur at all. 
