ORCHIDS. 295 



by signs, to give me a number of roots, but they did not grow well 

 in my garden. 



The more splendid forms of orchids are not terrestrial, but epiphytic, 

 growing on trees and rocks in their native country. The roots cling 

 closely to the trees or rocks, and fof that reason are called air plants ; 

 but I suspect that they draw much nourishment, and especially earthy 

 salts, from the plants on which they grow. During their period of growth 

 a nearly saturated atmosphere is absolutely necessary ; and at all times 

 of the year it is desirable that the air should be very humid. Probably 

 more orchids are killed by excess of heat, and a daily variation of the 

 dryness of the air, than from any other cause. They will not bear a 

 dry atmosphere, and heat combined with dryness causes certain death. 

 I do not pretend to grow exotic orchids, but I never refuse a spare bulb 

 from a friend. They grow with me like weeds, 'and so by the gifts 

 of many kind friends I have now more plants growing, in good health, 

 than existed in the country when I was born. The secret of my 

 success is to supply water by giving moisture to the air, and not to soak 

 the roots of the plants. The greater part of my orchids are grown in 

 the fernery, and the highest temperature which any of my plants get is 

 that which is necessary for the growth of cucumbers. Some of them, 

 as the Cypripediums and Dendrobium nobile, are grown in winter at a 

 temperature very little above freezing, and indeed occasionally they 

 may get a little frost, which, however, is to be avoided rather than 

 to be commended. All the epiphytic orchids shun the direct rays of 

 the sun, but rejoice in light. They never do well in a large house, 

 probably because the hygrometric state constantly varies. The part of 

 my fernery in which the orchids grow, has some light admitted from 

 the south ; but rows of trees are planted before- the glass, effectively 

 to intercept the direct rays of the sun in summer, though some of 

 the rays in winter are beneficially admitted. 



Most orchids do best if potted in broken pieces of pots inter- 

 mingled with the fibre of peat and sphagnum moss. By this 

 mode of growth the roots are always freely exposed to air and 

 moisture. . 



