CHAP, m.] QUANTITY TO BE GIVEN. 53 



space in which the roots are grown. Slightly- 

 soapy water given always to the leaves as well 

 as to the roots is also advantageous to plants 

 grown in the open air, but it should only be given 

 to them when they are in a state of vigorous 

 orowth. Watering over the leaves is also effica- 

 cious in suburban gardens in removing the soot 

 and other impurities which frequently rest on 

 the leaves and close up their pores. 



The quantity of water to be given varies, not 

 only according to the nature of the plant, but 

 to the state of its growth. In spring, when the 

 sap first begins to be in motion, and the young 

 plant is every day unfolding fresh leaves or 

 blossoms, it requires abundance of water ; as it 

 does when in flower, or when the fruit is swell- 

 ing. In autumn, on the contrary, when the 

 fruit is ripening, and in winter, when the plant 

 is in a state of perfect rest, very little water is 

 necessary, and much is positively injurious, as 

 being likely either to excite a morbid and un- 

 natural action in the vessels, or even to bring 

 on rottenness and decay. Water is necessary 

 for seeds to induce them to germinate; but 

 much of it is very injurious to young plants 

 when thev first come up, as it unsettles their 

 roots, and almost washes them away. The 

 roots, also, are at first too weak to imbibe 

 water ; and the plants feed on the nourishment 

 contained in the cotyledons, or in the albumen 

 of the seeds. It is when the second pair of 

 leaves has opened that water is required, though 

 it should at first be given sparingly. W^hen the 

 plant begins to grow vigorously, it requires 

 more food ; and, if it be then kept too short of 



