Novy.-DEc., 1g20.] THE ORCHID REVIEW. 178 
By J. T. BARKER, Orchid grower to His Grace the Duke of 
: CALENDAR OF OPERATIONS FOR NOV.-DEC. 
| Marlborough, Blenheim Palace, Woodstock, Oxon. 
HE two months now under consideration are usually the most dreary 
of the whole year, the days being short, with little light, and in many 
_cases the outside conditions are best described as miserable, especially in 
districts where fogs prevail. ‘The only thing that can be done in mitiga- 
tion is to keep the roof glass as clean as possible, and to maintain a 
proper balance of heat and moisture, admitting fresh air whenever possible. 
TEMPERATURES.—The temperatures of all the divisions will reach their 
lowest point during the present months, and should be kept, with slight 
variations, at the following figures :— 
East Indian house, 60° to 70°. 
Cattleya house, 55° to 60°. 
Mexican and Intermediate house, 55° to 60°. 
Cool house, 45° to 55°. 
The lower figures indicate the night temperatures, which should be the 
minimum, whilst the higher figures should be taken as the day temperatures. 
For some considerable time, the grower will have to rely on the heating 
apparatus for all the heat necessary to maintain the temperatures, and here 
may be mentioned one or two errors that are often made as regards the 
winter temperatures of Orchid houses. An excessive amount of fire heat is 
most detrimental to the plants, as it not only undermines their constitutions, 
but also dries up the compost, which entails unneccessary labour in water- 
ing to keep the plants from shrivelling. No harm will accrue should the 
temperatures in any of the divisions fall slightly below the figures given 
provided that at such time a dry atmosphere is maintained. 
ATMOSPHERIC MoIsTuRE requires special care at this season. A cold, 
damp atmosphere, like a hot dry one, must be strictly guarded against 
during the winter months, as either condition brings trouble. Everything 
depends upon the conditions we make for the plants, for even the most 
difficult subjects will thrive if placed in suitable quarters. The amount of 
atmospheric moisture required depends partly upon the amount of artificial 
heat given, and partly upon the condition of the plants. The outside 
conditions, and the amount of ventilation possible, have also to be taken 
into consideration. Many of the evils which Orchid growers are troubled 
with are attributable to a faulty atmosphere in the houses. Excessive 
moisture is likely to bring the much-dreaded spot disease, while thrip and 
other insect pests are encouraged by the reverse conditions. 
WATERING.—As regards the application of water to the compost, I must 
