WHY DO PLANTS DETERIORATE. 



be treated in a similar manner, and with alike good results. Those who grow the pansy 

 most successfully, always practice washing of the roots, though they may have no know- 

 ledge of the principles which should govern them in resorting to the process. Many gar- 

 deners do things because they have seen others do them, but they often cannot tell us why 

 or wherefore. 



Here, then, we have a few facts, and although they may not establish the opinions here- 

 in expressed, they at all events clearly demonstrate the existence of certain functions in 

 the roots of plants, by which refuse or foecal matter is discharged, and also that these re- 

 jections are highly injurious to the plant emitting them, if re-absorbed. We are, there- 

 fore, very naturally led to inquire, how shall these deleterious influences be neutralised or 

 destroyed.^ We believe it has been satisfactorily proved, that only to those of their own 

 species, are the rejections of plants injurious. To all others they are perfectly innocuous, 

 and very probably nutrimental. This establishes the propriety and necessity of attending 

 to the alternation and rotation of crops in the field and kitchen garden, and is a discovery 

 of no small importance to every cultivator of the soil. But how is it in the flower gar- 

 den? so widely different from growing vegetables. The majority of the plants are of pe- 

 rennial duration; therefore attention to this object is of still greater importance, and more 

 difficult of attainment; for no plant should be suffered to remain more than two or three 

 years in the same spot; if it does, degeneration is inevitable. It is especially to bulbs and 

 tubers these remarks will apply, for to them an occasional removal from the ground al- 

 together, is of very decided benefit; nor is this benefit derived solely from suspended ve- 

 getation, but likewise is due to a change of soil. Therefore, this latter fact should be ta- 

 ken into consideration and acted upon, if we desire the treatment to be as perfect as it 

 ought to be. 



When grown in pots, plants are far more materially affected by their own rejections, 

 because their roots are confined, and cannot extend themselves into uncontaminated soil; 

 yet much may be done in these cases to remove the difficulty, or to counteract its effects. 

 By some writers it has been declared, but not proved, that from the tips or extremities of 

 the rootlets only, is this excrementitious matter voided. This may be true or not; but 

 assuming it to be true, the importance of an annual repotting is too evident to need insist- 

 ing upon. To all gardeners it is a well known fact, that at the sides of the pot these root- 

 lets are always found in greater or less number. In repotting, the outside surface of the 

 soil is generally removed, and with it is taken away the injurious matter, in the place of 

 which we substitute fresh and sweet earth. So with a great many plants, we find near 

 the surface of the ground their fibrous roots. With these the operation of top-dressing 

 is practiced, and with the very best effects, only taking care to remove the top soil before 

 making the addition of fresh compost. 



But these are not the only means of neutralising or removing these unwholesome ex- 

 cretions. There are others of quite as much importance to the horticulturist or gardener, 

 to wit — a thorough exposure to the air, and a free permeation of water. The advantages 

 derived from the latter of these processes is too palpable to need further elucidation, and 

 it will readily be perceived, that in efficiently draining pots, we are doing something more 

 than is commonly supposed necessary. When the water is allowed to stagnate about the 

 roots, the plants becomes saturated, and in consequence, their rejections are more abundant. 

 A retention of this noxious feculence is thus inevitable, which is not only pernicious, but 

 very frequently destructive 



has been abundantly proved, that by freely exposing the soil to the varied influences 

 atmosphere, the excretions of plants contained therein are thereby either evapora- 



