292 WINDOW GARDENING. [CHAP. XI. 



the water to the roots ; and this it cannot do 

 when it becomes a blackened paste by being 

 saturated with water. At the same time, fre- 

 quent repotting is often absolutely necessary to 

 keep the plants in a dwarf compact habit of 

 growth, and to prevent them from being drawn 

 up. The way in which gardeners ascertain 

 when repotting is necessary is, by turning the 

 plant out of its pot with the ball of earth 

 attached ; and, if they find the roots look white 

 round the outside of the mould, then the plant 

 should be transferred to a larger pot ; but only 

 one size larger : afterwards it may be repotted 

 again if necessary, but always in a pot only a 

 little larger than the one it was taken from. 

 By persevering in this mode of treatment for 

 a good while, and never advancing more than 

 one size at a time, a plant may be grown to a 

 large size, and made to produce abundance of 

 flowers; while by the contrary treatment, that is, 

 suffering it to remain in a very small pot, or 

 shifting it suddenly into a very large one, the 

 stem will become weakened and elongated, and 

 the flowers will be few and very poor. In 

 short, on the skilful management of repotting, 

 or shifting, as the gardeners call it, a great deal 

 of the art of growing plants in pots depends. 



The best soil for plants in pots was formerly 

 considered to be peat, mixed with vegetable 

 mould and sand ; but it is now found that turfy 

 soil chopped loosely up and mixed with char- 

 coal roughly broken, is incomparably better. 

 In the case of heaths and other hair-rooted 

 plants, the soil should be mixed with Iroken 

 stones and pebbles, some of the latter bein£ 



