124 CULTIVATION OF POT-PLANTS 



holding water when the plants are watered. It is usual at Pera- 

 deniya Gardens to cover the surface of the soil in the pots with a 

 layer of small pieces of brick or sandstone, which has the effect 

 of preventing the soil from being washed out in the course of 

 frequent waterings, while also checking the evaporation of moisture. 

 After the plants are potted, a copious watering is given, and the 

 plants are kept for a few days in a dark room or under heavy 

 shade. A very common error on the part of native gardeners is to 

 use pots many sizes too large ; these are not only ungainly, but also 

 less suited to the health of the plants growing in them. Plants 

 look and thrive best in pots which are in proportion to their 

 size. 



The proper time for potting. This should be determined by 

 the progress of the plants and the condition of the soil, rather than 

 by any fixed seasons. Generally speaking, the best time for the pur- 

 pose is when the plants are commencing their more active periods 

 of growth, which usually occur at the commencement of the mon- 

 soon rains. The necessity for re-potting a plant may be ascertained 

 by turning it out of the pot and observing the state of the roots, 

 soil, or drainage. "It is a standing rule," said SIR JOSEPH PAXTOX, 

 "with experienced horticulturists that no plant should be allowed 

 a larger pot till the one in which it is growing is rilled with fibrous 

 roots." Frequently, however, before the pot is tilled with roots 

 the soil becomes sodden or impoverished, with the roots in an un- 

 healthy state, and the plant unable to make normal growth. This 

 condition is especially liable to be induced by the frequent watering 

 necessary in the tropics, and when it occurs the soil requires to be 

 entirely removed, and replaced with a suitable potting mixture. 

 (See below). 



Drainage of Pot-plants. There is no point of greater im- 

 portance than the drainage. In the great majority of cases when 

 plants are sickly, the cause is to be found in imperfect drainage, in 

 consequence of which the soil becomes sodden and sour. When- 

 ever this condition is suspected, the plant should be gently turned 

 out, and the drainage repaired as at first done, renewing the soil 

 also if necessary. 



Soil of Potting plants. The ideal soils for potting most plants 

 should consist of rich loam, leaf-mould and silver-sand, made up in 

 various proportions to suit the plants in hand. A peaty soil is con- 

 sidered specially suitable for ferns and plants of the Rhododendron 

 and Azalea family (though these may also thrive in loamy soils), while 



