Rusty Hinge 2 wrote:
I planted a seed tray full and about half came up and have survived to
date - including one in a small pot which I left outside by accident,
and it survived -4°C

I heard they survive -15C! It's a usual mistake to think 'exotic' plant
from warm climate cannot survive our weather. Cactus for example
survive very cold nights in the desert, some to -20C and can be found
as well as in South America than in north America.

I was re--re-re-reading a wonderful book last night, (as my exams
approach), called 'An hear to the ground' by Ken Thompson. Anybody
knows him? Because I must invite him for dinner. He says that we are
truly pushing our luck in England as we grow many plants from
California, south america, japan, new zealand and south africa. London
lies at a latitude of 51.5 degrees north and the corresponding
latitudes of tokyo, cape town, los angeles, santiago and wellington are
between 34 and 41 degrees south. Even with the Gulf Stream, we are
indeed trying our luck!