I have a large healthy-looking Christmas cactus which has only one bloom now. In the past it has been full of blooms. It has southern exposure in a bay window. What can I do to increase the number of blooms?
The lack of buds on your Schlumbergera may be due to too much light exposure throughout the year since it is in a bay window with southern exposure. Move it to a spot with more indirect light during the summer and fall months –“schlumbergeras should never be exposed to full summer sunlight”; the buds usually start to form in the early fall and “full flowering is initiated by the restricted light of the shortening days”.
Exposure to artificial light during the evenings (i.e. a lighted room) will also discourage budding and flowering. One can either cover the “budding plant with a black plastic sheet when the lights are switched on” or move the plant to a dark place “every day at twilight, and keep it there till morning”.