APRIL, 1914] THE ORCHID REVIEW. Toy 
CALENDAR OF OPERATIONS FOR APRIL. 
By T. W. Briscor, Late Foreman of Messrs. Veitch’s 
Hybridising Department. 
HROUGHOUT the present month careful attention must be paid to 
the shading and ventilation of the various divisions, as the weather 
is usually very changeable. We shall no doubt experience intervals of 
bright sunshine which will be injurious to young growth if unprotected, 
while a period of cloud, perhaps accompanied by a cold shower of rain, 
will cause a sudden fall in the temperature if due precautions are not taken 
by closing the ventilators. In regard to ventilation we must consider the 
local conditions—in fact these play an important part in Orchid culture— 
houses in sheltered situations can be more freely ventilated than those in 
exposed districts. Here it may be expedient to lower the blinds earlier in; 
the day, and a good plan for the amateur to follow is to run them down 
directly the leaves feel warm to the touch. The Intermediate: and:Cool 
houses must be particularly watched to prevent the temperature rising: 
excessively high, and when the thermometer records 65° in the former and 
60° in the latter the blinds ought to be lowered at once. They should 
remain down on these Cool houses till the sun has ceased to shine on the 
roof, but with warmer houses, especially those devoted to Cattleyas and their 
allies, the blinds must be removed an hour or so before that time, or as soon 
as all danger from the sun’s rays is past. 
A moist, growing atmosphere must be maintained in each department, 
and to this end the floors and stages should be damped down whenever 
they become dry. Each plant that is growing should be afforded a liberal 
supply of water, and any specimens that require top-dressing or repotting 
must be taken in hand before root action is very far advanced. Plants: 
pushing up their flower scapes ought to be kept just moist at the base, and 
such as Cattleyas, &c., may be neatly staked before the buds are fully 
grown. Such subjects as Oncidiums, and any Orchid that is showing 
signs of going back, must have their spikes cut off if the pseudobulbs begin 
to shrivel. The dwarf-growing Odontoglossum Rossii, Oerstedii, and 
Cervantesii are allowed a short season of repose as they pass the flowering 
stage, but they must not be dried off to any great extent. 
Most of the Pleiones are growing freely on a shelf or suspended near 
the roof glass in the Intermediate division, and must be given plenty of 
water until the bulbs are near completion. Coelogyne cristata will need 
water in small quantities till root action is evident, when any fresh compost 
can be applied. Frequent disturbance at the root is not advisable, but it 1s 
often possible to work in a little new soil between the growths without. 
repotting the plants. The Mexican Leelias ought to receive plenty of light 
