iO 



THE ORCHID WORLD. 



[October, 1913. 



only a few inches from the moisture-laden 

 soil, and, consequently, where little, if any, dry 

 air is to be found. The latter are generally 

 to be seen growing in well exposed positions, 

 where there is a constant current of air, and 

 little chance of a stagnant atmosphere 

 existing. The cultivator should always 

 carefully consider these essential points, and 

 endeavour to place his plants where they may 

 best succeed. It is no use blaming the 

 compost or finding fault with the nature of 

 the plant when the real cause of failure is the 

 surrounding atmosphere. 



Cypripediums are the best known examples 

 of terrestrial Orchids, and usually grow very 

 satisfactorily in houses which are quite moist 

 and shady. This atmospheric condition is 

 generally produced by the staging being 

 constructed in such a way that a considerable 

 quantity of moisture is at all times sustained. 

 The surface is covered with either sand, 

 broken coke, cinder-ash, or similar moisture- 

 holding material, and the plants are placed 

 directly on this, or elevated by being stood 

 on inverted pots, or on a light upper staging 

 composed of laths. By this means terrestrial 

 Orchids are cultivated under very similar 

 conditions to those of their native country, 

 for in both cases the foliage has a damp bed 

 beneath it, and is surrounded by a still, 

 moisture-laden atmosphere. 



It is, however, with the epiphytic section of 

 Orchids that opinions and methods have 

 altered. Formerly it was the custom to place 

 Odontoglossums and kindred plants on 

 staging similar to that described above, the 

 general belief being that a cool, moist 

 situation was alone sufficient for their needs. 

 But having regard to the light and airy 

 position in which they grow naturally, the 

 cultivator is now endeavouring to construct 

 the interior of his Orchid houses more with 

 d desire to reproduce the light, mountain-like 

 atmosphere in which these plants flourish so 

 well in their native land. Of course, many 

 can say they have already achieved this 

 satisfactory position, but even with them 

 there is no reason why still finer results 

 should not be obtained with improved 

 methods of stage construction. 



There now exists a general desire to 

 dispense with almost all under-stages in 

 houses devoted to cool-growing Orchids, the 

 only ones considered necessary being those 

 placed directly over the hot-water pipes in 

 order to counteract the dry and hot 

 atmosphere which would otherwise be created 

 in the house. In many of the large houses 

 there is a centre staging, under which hot- 

 water pipes are seldom placed, and even when 

 they are, there is a great amount of space 

 between them and the plants ; it is on these 

 stages that the healthiest Odontoglossums 

 are generally seen. A free circulation of air 

 round the plants is usually to be noticed when 

 no under-staging is used, and it is this light, 

 buoyant atmosphere which is so essential to 

 the welfare of cool growing Orchids. 



The thought may occur to some cultivators 

 that without the under-stages it will be 

 somewhat difficult to produce sufficient 

 atmospheric moisture. This, however, is 

 much easier than is generally imagined, for 

 by judicious spraying the moisture in the air 

 may be increased to almost saturation point. 

 The real difficulty lies in being able to 

 maintain this humid condition, for in most 

 houses there are not sufficient means to 

 regulate the varying climatic conditions to 

 the fine degree that cultivators of the present 

 day might wish. When once the atmosphere 

 has been rendered sufficiently moist every 

 care must be taken to prevent a too rapid 

 evaporation by excessive ventilation, and a 

 rise in temperature by insufficient shading. If 

 these two important points can be kept under 

 control there will not be much to complain 

 of when the under-stages are done away with. 



The amount of ventilation should be 

 regulated according to the outside weather 

 conditions. When the wind is cold and dry 

 great care is necessary to prevent it obtaining 

 direct access to the plants. It should first 

 be warmed and made moist by passing near 

 the hot-water pipes and over some moisture- 

 holding material. During rainy weather, and 

 when the outside temperature is not too low, 

 abundant ventilation may be given to the 

 cool houses with much benefit to the 

 occupants. 



