ON PLANTS. 133 



Mrs. B. In the midst of summer the plant, exhausted 

 by evaporation during the heat of the day, requires water 

 in the evening to revive it ; there is then no danger of 

 its suffering from frost during the night. In Switzerland, 

 where heat and light are much more powerful than they 

 are with us in England, it is generally necessary to water 

 plants both morning and evening : the earth is dry ; and 

 it is difficult in summer to provide for the immense in- 

 crease of the absorbing and evaporating functions. 



There are some plants which grow perfectly well on 

 ihe Alps, because they are, throughout the summer, wa- 

 tered by streamlets supplied by the melting snow : these 

 same plants perish on the Jura, or any other mountain 

 which is free from snow in summer, because they are not 

 furnished with so regular a current of water. 



In autumn, trees which bear pulpy fruits, such as the 

 peach and the plum, require a great deal of water to fill 

 out and to ripen the fruit. Fruits of a dry nature, such 

 as nuts and dates, do not need so much ; and the pre- 

 caution of watering in the morning is equally necessary 

 as in the spring, lest the plant should be surprised by a 

 frost during the night. 



Caroline. Grasses and herbs, I suppose, require more 

 water than trees ; for, consisting chiefly of leaves, they 

 must undergo a greater evaporation. 



Mrs. B. Yes ; and annual grasses the most of any. 



Seeds which are beginning to germinate, should be 

 watered very sparingly ; for the seed, feeding at first on 

 its own proper substance, is rather in want of air than of 

 water ; but as soon as it has put forth roots, and a stem 

 has sprung up, it will require a more plentiful supply until 

 the time of flowering, when it must again be restricted, 

 because the blossom is nourished by its own peculiar 

 juices elaborated by the leaves ; and when the seed ripens, 

 if it be of a dry nature, still less water must be given. 



The quantity of water depends, also, upon the nature 

 of the cultivation. You must consider what is the pro- 



741. Why in summer should they be watered at even ing 1 742. 

 What is said of watering them in Switzerland? 743. And of some 

 plants which grow on the Alps'? 744. What is said is needed by dif- 

 ferent trees to ripen their fruit in autumn'? 745. Why do grasses and 

 herbs require more water than trees 1 746. Why should seeds begin- 

 ning to germinate be watered sparingly; and how should the water after- 

 wards be proportioned 1 ? 



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