COOL TREATMENT OF ORCHIDS. IO/ 



must not be extended for too long a period. During the 

 growing season, no cessation of vigor must be encour- 

 aged; ample supplies of water both at the root and in 

 the atmosphere, are what the nature of the plants de- 

 mands. If the potting material be of the right kind, so 

 porous as to allow air to pass freely, and so fibrous as 

 not to become sodden, water may be given once a day 

 without injury. 



To promote a moist atmosphere the shelves of the 

 Orchid house may be strewn with wet moss, from which 

 the evaporation is highly beneficial. 



Insects should be kept under by the means given in a 

 former chapter. We must, however, remember that the 

 fumes of tobacco are injurious to many of the Odonto- 

 glots and other cool Orchids, causing them to shed their 

 leaves and as a general rule a miscellaneous collection 

 of Orchids requires to be fumigated with great care and 

 judgment. 



We have said that experience has latterly tended to 

 show that Orchids associate admirably with vines, and 

 that they may be successfully flowered and a crop of 

 grapes be grown in the same house. If we consider the 

 ranges of temperature we have given above for the regu- 

 lation of a cool Orchid house, we shall see they accord 

 well with those required in a forcing grapery. 



Experiments in England have shown that there are 

 comparatively few Orchids worth growing, which cannot 

 be cultivated under vines, and that many of the East 

 Indian species which have always been kept in the great- 

 est heat, do well under this regime. There are, however, 

 some species of Vandas, Aerides, and Phalanopses, which 

 cannot be so cultivated, though these in summer will 'suc- 

 ceed in a grapery. 



