Question

vanda dried bud   Dear Wayne,
A friend of mine has many many orchids, but recently she has been having a problem with her vandas. They shoot a bloom spike then, then the spikes dry up..All her plants are in a green house, she says that when the spikes shoot out she moves them to the opposite side of the green house, this section is more shaded. I personally think that her green house is too crowded, can that affect her blooms? I'm attaching a picture of the problem...
Thanks

Answer
Marita, there are many factors involved here. Some vandas, especially Vanda coerulea and its "bluish" hybrids, prefer cooler temperatures since V. coerulea is native to the mountains. This group of vandas are difficult to flower in tropical areas. Vanda culture in the greenhouse should be grown at mid-level.  I don't think the number of vandas is likely to be the cause of bud drop. Factors such as temperature, too low humidity, and stagnant air can all lead to this condition. Sometimes, when plants are moved while in bud, that change, can affect flowering because it is in that stage that buds are most sensitive to environmental change. If she has an evaporative cooler in her greenhouse, that could help.  Higher light levels can promote flowering but only to a point.  If those higher light levels are accompanied by higher temperatures, that defeats the gain from higher light levels. High humidity., along with good air movement, can be beneficial.