20 ORCHID-GROWEKS MANUAL. 



night, and from 65° to 70° by day; and as the days lengthen the 

 temperature may be allowed to increase, so that during the months of 

 May, June, July, and August the night heat may range from 65° to 70°, 

 and by day from 70° to 85°. 



Of late years we have had so many additions to what are called Cool- 

 house Orchids, that it is quite necessary there should be added another 

 house specially for their cultivation, and which we may call the New 

 Grenadan and Peruvian house. A plan of such a house will be found at 

 page 45. This will accommodate a great number of plants from various 

 high mountain districts, which may be grown together under the same 

 treatment. We do not recommend ordinary greenhouses for Orchids, 

 for our belief is, that very few Orchid growers will long uphold that 

 treatment ; and although we are told by collectors that many of the 

 species of epiphytal Orchids are found in localities where the temperature 

 falls so low at times that the plants are. frequently covered with hoar 

 frost, we do not think it expedient to subject them to such cool treat- 

 ment in this country, neither is it possible for flowering greenhouse 

 plants and Orchids to exist and do well in company with each other, for 

 their requirements in atmospheric moisture are so different, that one set 

 of plants or the other must fail. The house we recommend for the 

 Odontoglossums and other genera and species that come from similar 

 regions, and, consequently, require the same treatment, is precisely the 

 same as others, only it must be kept at a lower temperature, say from 

 45° to 55° in winter, and from 50° to 65° in summer. This house 

 should be well shaded from the sun with raised blinds (see p. 45), which 

 will help to keep the heat down, as too much heat is dangerous for these 

 cool Orchids. We have seen cool Orchids tried in nearly every aspect, 

 in some instances with sad results, but we consider the very best house 

 for the cultivation of the plants is one having a northern aspect, and the 

 finest plants we have ever seen were to bo seen in such an one. No fire- 

 heat will be required in summer except on cold or wet days and nights, 

 the object of then having recourse to artificial heat, being to keep the 

 house from getting too damp, dampness without the proper degree of 

 warmth being very detrimental to plants of this order. 



There are but few Orchids that will do without heat altogether, 

 except those that come from. North America and other cold climates, 

 and these will be treated on in a chapter by themselves. 



