What makes some plants more resistant to cold?
I'm curious, last night the temperature dipped to 8C (46F) and my Phalanopsis (orchid) was damaged by the cold temps while a Odontioda sitting beside it did not seem to be affected. The Phal was very healthy while the Odontioda was potted the day before having survived a 7 day trip (bare root wrapped in sphag) and the root structure was less than 2" (root rot I suspect). They are both considered a cool grower (ie need cool nights). I would have thought that the Phal with a fleshy leaf would have fared better than a thin leaf. This has brought the question what makes some plants more resistant to cold temperature then others?