Mar.-APRIL, 1920.] THE ORCHID REVIEW. 47 
which have recently flowered should be induced to rest, and should only be 
afforded sufficient water to keep them plump; if kept too wet there will be 
weak premature growths. 
GENERAL REMARKS.— Nature is exacting in her demands, and unless 
each detail in culture is performed at the proper time, the best results 
cannot be looked for. This in practice, may be hard to achieve, but those 
with an ideal are the most likely to succeed. Cleanliness in every detail 
should be practised, as a clean start medns} in most cases, a satisfactory 
ending. 
Sd VENTILATING ORCHID HOUSES IN EARLY SPRING. | 
WAS looking over an extremely well-grown collection of Orchids in the 
middle of March, and the grower, a man of mature experience and 
proved ability, said he had had more yellow leaves than he liked, and was 
looking round for the cause. We thereupon put our heads together and 
at last came to the conclusion that it was a matter of giving too much air 
so early in the year. The Odontoglossums had lost a good many leaves, 
and the Cattleyas also had more yellowing than was pleasant. 
The problem presented was this: The Odontoglossums were repotted 
in August and September, had re-established themselves comfortably in the 
new compost, and settled down into fine plump stuff with strong growths 
by, say, the end of November. From this period onwards, until February, 
their progress was quite normal—increasing growth, and added greenness 
and thickness of leaf, giving much hopeful promise for the lengthening days. 
And now, when the:new bulbs are finishing, and the days are as long as the 
nights, when spring is nearly here, why should leaves fade in increasing 
numbers? Leaves fall in the autumn, we argue, not in the spring. 
The past winter was exceptionally fine; and the spring-like, sunny 
weather of February gave tempting opportunities of opening the ventilators, 
and perhaps those opportunities were too well used. A high inside 
temperature caused by the sun on a cold, or even temperate day, should 
not be the signal to throw wide open the ventilators, but even the best of 
us are liable to make mistakes ! 
This has been a season when blinds were wanted early, and it is always 
safer to shade Odontoglossums for an hour or two on sunny days during the 
latter half of February, for the old leaves are particularly sensitive at 
this season. . Permanent shading is not to be recommended in any Case, 
as there are so many dull days in the year that are thereby made doubly 
dull,-and in these early days, perhaps, only a few hours a week will make 
for safety. To stipple a house over. with permanent shading in February is 
