DaveP wrote:
Jeff Layman wrote:

Sadly, there is little if any correlation between "a few degrees of
frost" in the USA and what we might experience in the UK. The major
difference is what happens in the summers, if that doesn't sound too
odd. Over there, they often experience summers with many days above 35°C
- sometimes above 40°. That apparently hardens the wood of certain trees
and shrubs which allows them to withstand winter cold better than here.

Even when you get Bauhinias to over-winter successfully, they need hot
weather to flower well. I've had B. yunnanensis growing here for
about 10 years and it is an indifferent performer unless we have a
prolonged hot spell. I completely gave up with B. purpurea, which
survived winters well but only gave the occasional flower right at the
end of summer.

I've been growing B. yunnanensis for 3 years from seed. Still pretty small,
and can't seem to make up its mind whether it's a shrub or weak climber!
Interesting that it needs prolonged hot spells to do anything, but typical
of "inland continental" plants.

But is your B. yunnanensis hardy enough to survive outside? I still keep
mine in a frost-free (1 - 2°C) greenhouse, and it is pretty much deciduous
even under those conditions.

--
Jeff