= 
JULY, 1913.] THE ORCHID REVIEW. 205 
kinds, as they do not possess in a like degree the power of drawing 
supplies from the atmosphere. This is an interesting faculty which is 
being considered more and more by growers of the present century. The 
ability of epiphytal kinds to take up little or much moisture is mainly 
determined by the amount of air they receive, and also by the light and 
description of the house in which they are grown. Light and air naturally 
enable any plant to take up more moisture by means of its roots, and these 
organs of nutrition must be in a suitable medium. Any great excess of 
moisture will cause young roots in course of formation to die prematurely, 
-and often times result in the death of the older ones. Rain water is 
‘preferable for all plants as being purest and most natural, and Orchids 
‘should receive no other, especially epiphytes, for in their natural state they 
can never experience the effect of any other kind. 
With regard to the roots of Orchids, and compost for same, most 
Orchids, when growing naturally, have their roots in a great measure 
exposed to the air on trees and rocks to which they cling, with the head 
of the plants extending to the light, and generally where decomposed 
vegetable matter has accumulated within reach of their roots. It is 
obvious, therefore, that if the roots of such epiphytes are potted in a 
compost which is at all adhesive, they will very soon perish; at the same 
time, loosely-potted plants do not grow so strongly as when a more or less 
substantial material is employed, and firmer potting practised. English 
peat of the best quality for epiphytal Orchids is now almost unobtainable 
in large quantities. From the early ‘nineties there has been an increasing 
scarcity of this material, but it is only about ten years since osmunda fibre 
from America and polypodium fibre from the Continent have been proved 
to be satisfactory substitutes. These materials have gradually found favour, 
and are now extensively used as a rooting medium for Orchids. The early 
€xperiments, which led up to its extensive use, were carried out at 
Westonbirt. Other necessary materials employed in the potting of Orchids 
are good fibrous peat, fresh sphagnum moss, clean crocks, charcoal, and 
coarse silver sand. Some good turfy loam of a not too sandy description is 
required for strong-growing plants such as Cypripediums, Calanthes, 
Cymbidiums, Phaius, Pleiones, and other kinds. 
The process of potting Orchids is not difficult, and cultivators should 
‘Make a golden rule of never to pot a plant until the roots show signs of 
activity. When repotting is done just before new roots actually do appear, 
the compost is fresh and sweet for them, and they seldom fail to take 
advantage of it. There is no special season for potting Orchids, but the 
observant cultivator watches his plants, affording them fresh food when 
they need it. Teak-wood baskets, perforated pots and pans, and common 
garden pots of the usual pattern are all used as receptacles. Of the three I 
