Dendrobium nobile is a deciduous species from Asia. It has been hybridized a lot to get all sorts of great coloration, and those hybrids are referred-to as "noble-types".
I am not a grower of dendrobiums, but I am aware that the D. kingianum (not a nobile-type) needs a rest. However, "rest" is not really defined as "cold" as you suggest. Sure, a cool spell is part of it, but the important aspect is no fertilizer whatsoever.