| What you are seeing is damaged roots. Whether they were damaged by you or more likely came that way is hard to say.
Also this is just the beginning of growing season and there can be few signs of root growth this early.
Humidity is not that important a factor for Cattleya as you might believe. It is possible that low humidity required more frequent watering but it does seem that every 7-10 days would be a problem indoors when the plant was not actively growing.
One problem is that you may have been expecting too much this early in the season.
Since you have cut all the roots, grow the plant as you would a bare root plant. Prepare a pot with bark and use a pot clip to hold the plant on top of the medium. Do not bury the rhizome. Water sparingly until you see new roots come out of the leading pseudobulb. You may lose all the leaves on the old bulbs and need to remove them in a few months. This may require re-potting into a smaller pot.
I am Guessing - If your plant was in bloom when you bought it you should have seen new roots growing shortly after the flowers died. If you did not, then the plant may have been in serious trouble before you bought it. Cattleya should be re-potted after flowering.
It is not rot or fungus as the symptoms are different. On Cattleya fungus (rot is just a common name) is seen as black blotches spreading rapidly across the leaf. Shriveled and curling leaves are the result of insufficient water - not necessarily that you watered too little - but that the roots of the plant were damaged to where they could not absorb the water.
It is important to understand the difference in Orchid families and how they indicate distress. Shriveled leaves on Phalaenopsis can be from over or under watering, but on Cattleya it means damaged roots.
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jerry  |