THE ORCHID REVIEW. 87 
CALENDAR OF OPERATIONS FOR MARCH. . 
By W. H. YouNG, Clare Lawn, East Sheen. 
THE temperatures of the warmer divisions should be gradually increased as 
the month advances, emphasising the word ‘ gradually,” and see that it be 
carried out, not adopting a course diametrically opposed to the one that has 
been in vogue during the last few months ; for even if we have fine weather 
at the beginning of the month, we are not yet out of the wood, and so we 
should proceed to raise the temperatures, and adopt other well-known: 
methods to produce animation in the plants in a very cautious and well- 
considered manner. With the Cool houses it will be necessary to still work 
upon the same principles as heretofore, viz., to make use of every method 
and contrivance at our disposal to do away with more than the requisite 
quantity of fire-heat ; but as the days are likely to be warmer, more air can 
be admitted, which will neutralise to some extent the ill-effects of the fire- 
heat required to maintain the night temperatures. The direction and force 
of the wind, the position and design of the ventilators, have all to be taken 
into consideration when giving air. The best design for ventilators in the 
walls are those which work on a swivel, so that when it is only possible or 
necessary to admit a small quantity of air, it is deflected, and more likely to 
come into contact with the hot-water pipes before reaching the plants. 
Those in the roof, if on both sides, should at this season be only opened on 
the south side; but if the houses have been constructed as some here ‘are, 
with the ventilators on the north side only (a sensible builder, this !), they 
should be used very sparingly, especially in windy weather. Shading will 
be called into requisition again soon, and as one does not know how soon 
that may be, the different kinds of blinds or other shading apparatus should 
be put into proper working order, not necessarily for immediate use, but. for 
any emergency that may arise. Under normal conditions, the general 
occupants of the Cattleya and Mexican houses will not require shading until 
the end of this or beginning of next month, or the Dendrobiums, but 
- Cypripediums, Phalznopses, Miltonia Reezlii and vexillaria, Masdevallias, 
and other soft and thin-textured leaved Orchids will be sure to need a little 
_-—protection from the mid-day sun if we are fortunate in having a bright and 
clear atmosphere over our heads. 
In some cases new blinds will be needed, and the question will be forced 
upon our minds what kind of blind is the best; and if wanted for any 
house where Phalenopses, Cypripediums, Masdevallias, Miltonia Reezlii, 
and other kindred subjects are not grown, there is only one answer to that 
question—viz., lath roller blinds. These undoubtedly are the best for 
Cattleyas, Lelias, Epidendrums, Dendrobiums, Odontoglossums, and _ hosts 
of other Orchids, as has been proved by more than one experienced Orchid- 
