May, 1903.] THE ORCHID REVIEW. 139 
CALENDAR OF OPERATIONS FOR MAY. 
By JoHN Mackay, The Gardens, Highbury, Birmingham. 
Coot HousE:—The temperature in this department should now be kept as: 
low as possible, both night and day, for Cool-growing Orchids are much 
injured if grown too warm. The temperature must be kept down in the 
day-time by heavily shading. The blinds should always be raised six or 
nine inches from the glass, the power of the sun upon the glass being thus. 
greatly reduced. No plant in this department should now be allowed to 
suffer from drought, but, on the other hand, avoid keeping the compost in a 
sodden condition. Give each plant a thorough watering when showing. 
signs of becoming dry. A slight syringing overhead is advantageous after 
a warm, dry day, but for this purpose clear rain water is essential, and none 
other should be used. Ventilation in abundance should now be continually 
given. The damping down of the houses should now be done three times 
daily, and it should be done well, a good supply of hard water always being 
at hand for this purpose. There are several cool-growing species that will 
be in good condition for repotting this month. Among them are more of 
the Odontoglossum crispum type that have bloomed and are starting to- 
grow. Then there are many of the cool-growing Oncidiums ina similar 
condition, such as O. macranthum, O. tigrinum, O. ornithorrhynchum, O. 
cheirophorum, O.varicosum, O. Forbesii, O. crispum, and any others that 
may be starting to grow. A suitable compost consists of two parts of leaf 
mould, one of fibrous peat, and one of chopped sphagnum moss; pot rather 
firmly, and surface over with a layer of chopped moss. Some of the smaller 
growing kinds of Masdevallia may also be repotted. This genus delights to: 
grow in the coolest possible house during summer, but during winter the 
temperature should be a little higher; in fact the Intermediate House 
temperature is none too high. Too much damp and cold is the cause o 
the leaves dropping off or becoming spotted with black marks. The pretty 
little white autumn-flowering species, M. tovarensis, should nowbe attended 
to, and repotted if necessary, and also any of the others that have passed 
out of bloom. Masdevallias of the more showy type, such as M. Harryana,. 
M. ignea, M. X Shuttryana, M. Veitchiana, and M. Shuttleworthii, are 
now making a brilliant show in this department, intermixed with Odonto- 
glossums, Oncidiums, Epidendrum vitellinum, Ada aurantiaca, and the: 
pretty Cochlioda Neetzliana. No fire heat should now be required in this. 
department. 
INTERMEDIATE House.—The temperature in this department should! 
now be as follows :—Day, with sun heat, 75°; without sun, 65° to 70°; 
night, 65° ; morning, 60° to 65°. Shading will be necessary to keep down: 
the temperature, and this department should be kept very moist by damping. 
