Jan.-Fee., 1919.| THE ORCHID REVIEW. u 
existence this is easily managed, as the air passing over the hot water pipes 
becomes warm before coming in contact with the plants. If bottom venti- 
lation does not exist, some trouble will have to be taken to recharge the 
houses without causing draughts, which are most detrimental to all forms 
_ of plant culture under glass. There was a time when growers were afraid 
to admit air to their plants, with results which at the present day are well 
known. There are not many days in the year when it is not possible to 
have the bottom ventilators open, if only for an hour or two, in spite of the 
restrictions on fuel consumption. During boisterous weather they may 
remain closed, as then sufficient fresh air finds its way into most structures. 
A dry stuffy atmosphere must also be counteracted by judicious damping of 
the floors, &c., thus providing a proper amount of moisture. Some houses 
are naturally drier than others, and will need damping more frequently ; 
again, some’situations are more humid than others, hence the necessity of 
careful observation in this respect. A genial atmosphere must be main- 
tained at all times, by a proper balance being kept between heat and 
moisture, and there are few things Orchids resent more than over-heated 
pipes and a parched atmosphere. 
WATERING.—Water must now be applied to the compost with great 
discretion, as it is much easier to get a plant too wet than to get it dry 
again. It is impossible to define the amount of moisture each individual 
plant should receive, but a safe course to pursue is as follows: All growing 
plants should have water applied to them whenever they become dry, whilst 
those at rest should on no account be allowed to shrivel. The effect of 
excess in either direction is injurious, as both mean the loss of roots and 
vitality. 
CATTLEYAS AND ALLIES.—Such plants as produce flowers at this early 
season should receive all the light possible. Rather more water than they 
have been receiving since the completion of growth is essential to develop 
their flowers, reducing the supply again directly the latter are removed, and 
continuing this course until new growths or roots are observed to be pushing. 
This treatment also applies to any of the hybrids that may now be develop- 
ing flowers. Vigorous, well-ripened plants should not be allowed to suffer 
for want of water at this season, but should be kept plump and healthy. 
On the other hand, too much water, either at the roots or in the atmosphere, 
is detrimental, and may cause black spot to develop, especially during spells 
of cold weather. 
DENpDRopIUMS.—The flower buds on many of the deciduous and semi- 
deciduous varieties are now pushing, and more water at the roots will be 
required than they have received since the past season’s growth. was 
developed, but even now the plants should be allowed to become dry before 
giving water. When the outside temperature does not fall below 40°, 
* 
