Question
I have a bunch of white orchids that have brown spots on the blooms and the leafs have all died off and dried up.  What could be the problem?

Thanks,

Steve

Answer
Steve, the spotting on the flowers is due to excessive humidity/moisture on the flowers, especially during the night, In the future try to avoid watering late in the day and try not to get water on the flowers and/or buds. Similarly, I suspect that leaf loss is due to root rot, again, from a potting mix that has broken down and retains too much moisture.  This may not have anything to do with your growing practices but, perhaps, from the condition of the plant when you got it.  Some commercial growers are just concerned with the short-term health of the plant and fail to provide plants that have been fresly repotted in a fir berk based potting mix.  The use of moss in potting mixes is to be discouraged as the moss tends to compact shutting off the air supple to the roots and preventing the potting mix from drying out.

I recommend that you cut off the flower spike and unpot the plant.  You will probably find roots that are "mushy" and dead.  Healthy roots are firm and turn green when wet. Two conditions are necessary for you to revive this plant.  First, you must have a viable growing point from which the leaves arise. If you lost all of the leaves, there is a good chnce that that growing point died and the plant will be unable to send out new leaves.  If the growing point is viable, you must have at least one or two healthy roots. Under the best of circumstances, it is likely to take a couple of years to grow the plant back to health after repotting it to fresh potting mix.  Reputable dealers may be willing to replace the plant if you recently purchased it (Home Depot used to have such a policy-- I don't know if they still do).