204 THE ORCHID REVIEW. [JULY, 1913- 
ORCHIDS: THEIR POPULARITY AND CULTURE. 
(Concluded from page 111). au 
ANOTHER important requisite in the culture of all Orchids is full and free 
ventilation, not only during the daytime but also by night, when it can be 
managed without creating a draught. It needs only to be considered that ' 
the greater portion of Orchids are epiphytes, growing, in their natural 
conditions, on the branches of trees and, in many cases, isolated positions 
on hill sides, to convince anyone that they are subject, in their native 
home, to a circulation of air, therefore under cultivation they should be 
supplied with abundance of this very important element, in fact, it is 
absolutely necessary, for as it is with light so it is with air. If there is any 
shortage in the supply of either of these factors the whole substance of the 
plants, leaves, bulbs, and roots, are deficient in the solidity indispensable to 
keep up a healthy existence. Judicious use, therefore, of the ventilators of 
the houses is always important at all seasons of the year. To freely 
ventilate the houses on hot, sunny days, and to admit air only by a chink 
on dull days and by night is, to my mind, a most absurd practice. This 
close-shutting system, especially at night, with a view to keeping up 4 
desired temperature, produces on plant life an amount of mischief difficult 
to calculate. I never could see the reason why ventilation, if so beneficial 
during the daytime, should not be equally so during the night. Fresh air 
all night, with reasonable temperature, must be more conducive to health 
and vigour than anything approaching a stuffy atmosphere. 
- The proper atmosphere of an Orchid house is one in which the air is 
constantly changing, keeping the temperature in accordance with the 
occupants ot the house, and sufficient moisture in the air to create @ 
buoyant feeling, so heat, air, and moisture, to use a familiar expression, g° 
hand in hand. Whenever the temperature permits of free ventilation the 
atmosphere requires to be replenished in a like ratio. A constantly changing 
and well-balanced temperature is one of the most important points in the 
culture of these beautiful plants. 
Speaking of moisture brings me to a very important matter, and that is 
the watering of Orchids. There is no more important operation connected 
with their culture, and none oftener mismanaged. Who will say this does 
not apply to the cultivation of all plants in pots under glass? Even the 
most experienced practitioner needs all his wits about him if the work is tO 
be done with despatch. In watering a mixed house of Orchids this is 
especially the case, even when all are in full growth, allowance always 
being necessary for the condition and quantity of compost about the roots, 
and the comparative vigour of the plants. The majority of the terrestrial 
kinds require proportionately more water at the roots than the epiphytal 
at 
