I have several orchids, different varieties, but I have one that produces buds but they wither and fail to open. I treat it exactly as the others - i.e in the bathroom after flowering, water and feed regularly. This orchid was a deep purple when brought. It grows new leaves and currently has two stems with mature buds which have looked ready to open for several weeks. Meanwhile, the small buds have dried up and I have removed these. This plant did this last flowering season and looks to be going the same way. Do you have any advice? I currently have three different plants flowering.
Bud blast is quite common and generally is due to watering issues, temperature changes, lack of humidity or to much fertilizer at the blooming stage.
Here are some links with more information.