How to save a Dendrobium 'Samurai' (Sameri) - partly dying and new growth

[estación seca]

Antelopes want to be warm and moist all year. They should not dry completely. Your fall/winter/spring days and nights outside are too cool for them. Many of your spring/summer nights are also cooler than they prefer. I would keep this one in the warmest spot you have. I think your plant's problems derive from being too cool and not being watered often enough.