370 THE ORCHID REVIEW. [ DECEMBER, 1903. 
CALENDAR OF OPERATIONS FOR DECEMBER. 
By JoHN Mackay, The Gardens, Highbury, Birmingham. 
To those who have had experience in the cultivation of Orchids it is well 
known that abundance of light is indispensable to their well doing. We 
have now reached the period when the least amount is at hand, and it 
becomes necessary to utilise it to the best advantage. Those that have the 
good fortune to be located in rural districts have the advantage over those 
in the neighbourhood of large towns in this respect. Daylight with the 
latter is a scarce commodity ; hence it is necessary to constantly keep the 
roof glass as clean as possible, in order to get all the light available. 
The temperature of all the divisions will reach their lowest point during 
this month, and should, with little variation, be as follows :—— 
Warm House.— Day, 74°; Night, 68°; Morning, 64°. 
Cattleya House.—Day, 68°; Night, 64° ; Morning, 60°. 
Intermediate House.—Day, 62° ; Night, 58° ; Morning, 55°. 
Cool House.— Day, 58°; Night, 54°; Morning, 50°. 
Unfortunately, for the plants and their growers, houses are often used 
for Orchids that were originally used for another and cooler class of plants, 
consequently the piping is insufficient to insure the requisite degree of 
warmth without unduly heating the pipes; hence on the occasion of hard 
weather a dry and scorching atmosphere is created, altogether unfitted to 
the welfare of the choice and oftentimes costly inmates. How to proceed 
under these circumstances is often a puzzle to the grower. In the first place 
he tries to maintain the temperature, and then, in order to counteract the 
dryness of the air, throws water about to produce moisture, which usually 
ends in remedying one evil and promoting another. Under these circum- 
stances it is much better to keep the temperature lower during a spell of 
severe weather, so that the above state of things does not occur. The evil 
of over-damping during winter, when fire heat is so much in evidence, i$ 
two-fold in its action; first, we get a superabundance of moisture ir the 
air, and secondly, the moisture condenses on the bars and rafters, forming 
drips, which, except under the most favourable circumstances, falls on the 
plants, and causes irreparable damage. In most modern houses drip-proof 
rafters and bars are used; these carry off the condensed moisture, but even 
then a surcharged atmosphere is not at all beneficial at this season, this 
often proving the forerunner of the much-dreaded ‘‘ spot.” The wisest, and 
in the end the cheapest, method is, when a new house is being built, to 
place under the stages a much larger quantity of piping than is usually 
considered sufficient, for the greater the heating surface, the lower propor- 
tionately will be the temperature of the whole, yet the aggregate will be 
sufficient to raise the temperature of the house to the required degree, 
te eee bs 
