Dave Poole writes
It appears to be more cool tolerant than Ficus elastica and may even
cope with being grown out of doors in the mildest regions of the UK. I
received a seedling from a strain that is supposedly cold tolerant and
it has grown away quite well this summer. It has coped with our winter
far. Fingers crossed.

Mine copes with temperatures down to 0 deg C in a slightly heated
greenhouse. It likes to be watered throughout winter - droops its leaves
if it gets too dry.

"Plants for a future" lists it as being OK outside in Tresco but thinks
it's unlikely to survive on mainland.

It's attractive to scale insect, but otherwise isn't troubled by pests.
--
Kay