| It is hard to make generalizations on the results of a few plants.
Drying can cause buds to drop as well as too much moisture. Air circulation is always a factor.
All the factors you mentioned can have a factor in the result and just having orchids will cause some to drop buds. Exhaust flumes can effect the plants even when you do not smell the exhaust.
Their are a number of insects that can suck on buds causing them to drop.
any temperature change can cause it.
It comes down to how many plants are losing buds out of the total amount you have. At the end of the summer most of my orchids had a short life on their flowers and many buds did not develop. This happened more in the sheltered areas where I tried to protect buds on plants for sale while the one left out in the open air did better. It was very hot with big temperature swings.
If it is a couple of plant in a large group, then it is just normal. I find about ten percent losses are common.
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jerry  |