74 THE ORCHID REVIEW. [May-JUNE, 1920. 
By J. T. BARKER, Orchid grower to His Grace the Duke of 
: ee UBS OF OPERATIONS FOR MAY-JUNE. | 
| Ghaclnoonenk, Blenheim Palace, Woodstock, Oxon. 
ITH the advent of May we may safely assume that more genial 
conditions will prevail, and the summer treatment of Orchids should 
commence. The plants have already responded to the increased light and 
sun heat of the past few weeks, and in each division have now commenced 
to grow freely. Every inducement should be given them to continue, so 
that they may build up strong healthy pseudobulbs by the end of the 
growing season. The temperature should now be raised a few degrees in 
each department, and during bright weather will attain the maximum for 
the year. This is to the benefit of the warmer divisions, but Cool house 
Orchids are soon injured by excessive heat, and during hot weather must be 
-kept as cool as possible by the use of a greater amount of humidity, and the 
judicious use of the ventilators and blinds. 
ATMOSPHERIC MOISTURE.—The advancing power of the sun and the 
general increase in temperatures necessitates the use of more moisture in 
the houses, not only to make those conditions which are so essential to 
satisfactory growth, but as a preventative against insect, pests, which soon 
increase rapidly in a dry atmosphere. Unsuitable conditions bring their 
respective troubles, and a proper balance between heat and moisture must 
be maintained to secure the best results. It will easily be observed by 
anyone if the proper conditions are being maintained, for when the houses 
feel uncomfortable to the cultivator it is the same tothe plants. Everything 
depends upon the conditions made for the plants, hence the necessity of 
close attention to what might otherwise appear a small matter. Spraying 
and syringing may now be indulged in on bright days, but only soft, tepid 
water should be used for this purpose. Care should be taken that the leaves 
have time to dry before night. 
WATERING must be done at all times with care, as so much depends on 
the individuality and condition of the plant. The danger of over-watering 
is hardly present at this season, when growth is active and the compost full 
of roots, but at other times an excess of water has the effect of killing the 
roots by souring the compost. On the other hand, an inadequate supply of 
water is a hindrance to free growth, and continual dribblings on the surface 
is most harmful. When water is applied, it should be sufficient to soak the 
compost through, and then the compost should be aeons to dry out 
thoroughly before it is applied again. 
_ VENTILATION.—During hot weather the ventilation of the Cool house 
will need considerable attention, as the humidity of the atmosphere must be 
