Drainage 



causes which militate against good drainage even 

 when it is thought to have been efficiently provided. 

 Drains in the open ground often become filled with 

 tree roots or broken in their course so that the 

 channel becomes filled with earth and choked. The 

 air supply to the roots of plants in pots is not in- 

 frequently interfered with by the use of dirty pots, 

 of pots much too large for the plants in them, by 

 worms carrjring earth into the drainage, and by 

 standing plants over the week-end with water about 

 half-way up their pots so that they shall lack nothing. 

 The use of fancy pots in which to stand the ordinary 

 flower-pots often leads to the same trouble, which 

 usually manifests itself by the tips of the leaves 

 becoming brown. Glazed pots render watering 

 much more difficult than ordinary flower-pots, and 

 novices often come to grief in using them, as did the 

 artistic (?) individual who painted the flower-pots 

 with a bright green paint and so fiUed up all the 

 pores through which air was wont to pass. 



Plants in iU-draiiied and sour soil often indicate 

 the condition by the unhealthy yellowish tiat of 

 their foliage. Pallor is almost always a symptom 

 of ill-health, and if accompanied by stunted growth 

 and by brbwn tips to the leaves, will usually be 

 found to be due to interference with root activity 

 through iU- drainage. Some other causes leading 

 to interference with root -action produce similar 

 symptoms, but that is the most common. 



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