Lack of flower spike initiation may result from: 
(1) 
Poor cultural practices which failed to produce a healthy new 
bulb in the normal growing period. Root damage from disease, 
salinity, or poor aeration could be factors. Lack of sufficient fer- 
tilizer or moisture could be factors. Proper control has been 
outlined. 
Low light intensity or very short days, due to morning and eve- 
ning heavy shade, could result in insufficient storage of foods. It 
it frequently the practice of orchid growers to supply enough light 
to keep the plants slightly on the yellow side. In terms of light 
JUNGFRAU, ‘Snow Queen’ 
Silver Award Cym. Soc. ‘51; F.C.C., A.O.S. ‘52; A.M., R.H.S. ‘35 
intensity, a minimum of 2000 ft. candles should be maintained 
with the maximum in the vicinity of 4000 ft. candles. 
Too high a night temperature in the period of initiation. From 
July on, the plants should be exposed to as much cool night tem- 
peratures as possible. Although the “critical” temperature is not 
known, and is probably not the same for all crosses, it does seem 
that temperatures below 50 degrees F. are able to affect flowering. 
The minimum number of hours of low temperature is probably 
another requirement, being variable with the various crosses. 
Practical control of this phase usually is confined to providing 
maximum ventilation plus some evening and night syringing. 
During this important period, plants should not be kept in heated 
greenhouses or indoors. 
tl) ae 
