22 



THE CULTURE OF POT-PLANTS 



cause of disease. The slime which covers them offers a 

 resting-place for germs, and also prevents the air from 



Fig. 8. — Frozen Ricbardia suspended upside down so that when it 

 thaws the leaf stalks may stiffen straight. 



reaching the roots. It should be washed off with soap and 

 water applied with a hard brush, and if that does not get 

 rid of it, a piece of brick should be used. If, however, the 

 pots are very old, and especially if they are cracked, it is 

 much better to transfer the plants to new ones, which should 



