Pacific Northwest Gardening: Epiphyllums in Western Washington?, 1 by

wrote:
Yep, they can definitely handle in the 40's. My greenhouse is 'cool' in the winter and will get down into the high 30's, but never low enough to do damage. The epi weathers this very well. I have it planted in a fast draining mixture that is actually an orchid mix. Found a photo of the whole plant. Wish the setting were more picturesque. Don't blame you one bit for wanting to get mature specimens. They do take a while to get big.