THE GREEN-HOUSE. 



149 



care be taken in the performance, and in regulating 

 the elements of growth, as heat, light, air, water, &c., 

 afterwards. 



These maxims refer chiefly to the green-house; 

 and perhaps they may expand a little the ideas of 

 such readers as may be but slightly acquainted either 

 with practical gardening or vegetable physiology. 

 To the gardener who is ambitious of operating on 

 just principles, they will be of some assistance in 

 enabling him to generalize his ideas on different parts 

 of his art. 



Sect. III. Management of Green-house Plants in 

 Summer, 



Whether the erection of the green-house was com- 

 pleted and stocked with plants in the autumn or 

 spring, the first important operation required to be 

 performed in their management is the process of 

 shifting, and this almost always takes place in the 

 beginning of the summer quarter. 



Shifting is the transplanting of the plants from 

 one pot to another ; generally from a smaller pot to 

 a larger, but sometimes to a smaller pot, or to one of 

 the same size. The common object is to strengthen 

 the roots of the plant by a supply of fresh mould; 

 and an occasional object may be to change the man- 

 ner of growth of the plant by a change of mould and 

 a change of pot. All plants in pots require shifting 

 occasionally, for so small a quantity of earth as a pot 



