My little brother recently bought his first dendrobium a week ago and it has started to yellow. Is it entering dormancy? Is it shock from transportation? Do I need to do anything or should I leave it alone? Thank you for your time and help
I suspect that it is just a bit of transportation shock. It very likely was just stuck in that pot with sphagnum to keep it hydrated for shipping purposes. Likely a very recent import. Keep it moist but not soggy, it does not need a dry rest, doesn't go dormant (It's a tropical, lowlands species) It will, however, bloom on bare canes so don't worry about the leaf loss. Just give it normal warm-growing Dendrobium care and it should be fine. It may take a bit of time to adjust, that's normal.