18 PRESENT-DAY GARDENING 
ture during the day and that experienced at night, the differ- 
ence in some parts being that between an excessively hot day 
and a chilly night and early morning. These cool conditions 
at night are absolutely necessary for the well-being of the 
plants, and in their absence the plants suffer as do human 
beings during the progress of a heat-wave, which often kills 
many people. Therefore it must be urged that at night the 
temperature must be from 5° to 10° Fahrenheit lower than 
the day temperatures. This condition is difficult to get 
during hot weather, but it is necessary. Although a scale 
of temperatures throughout the year must not be taken to 
mean that a little more heat may not be allowed occasion- 
ally—as, for instance, by sun-heat, which is beneficial— 
nevertheless it is better to have a scale to form a basis, and 
especially to emphasise the lower temperature at night. 
Table of Temperatures for Orchid Houses 
Warm House, East attleya or r 
Months. Indian. nee House. Gliese House. 
Day. Night. Day. Night. Day. Night. 
January . ‘ 65-70 60 60-65 55 50-55 45 
February ‘ 65-70 60 60-65 55 50-55 45 
March . ; 65-70 60 60-65 55 55-60 50 
April. 7 65-70 60 60-65 55 55-60 50 
May. . 70-75 65 65-70 60 60-65 55 
June. ; 75-80 65 70-75 60 60-65 55 
July é ‘ 75-85 65 70-80 65 60-70 55 
August . s 75-85 65 70-80 65 60-70 55 
September . 75-80 65 70-75 60 60-65 55 
October . . 70-75 65 65-70 60 60-65 55 
November . 65-70 60 60-65 55 55-60 50 
December. 65-70 60 60-65 55 50-55 45 
Degrees Fahrenheit. The higher day temperature should be obtained by 
sun-heat when possible. 
