Q.Why Do The Flowers And Buds Fall Off?
I have a cactus which flowers twice yearly but, although it has loads of buds, as soon as the first few flowers open, then the buds start dropping off many of the flowers start to droop quickly.
Certified GKH Gardening Expert
It is usually an environmental issue, i.e., inconsistent watering, temperature fluctuations, lack of humidity. This article should help pinpoint the issue: