From the poster's email address, I suspect he is speaking of the
"Durham area" of the UK. If so, even if we told him the low temps here,
we'd have to convert to Celcius or whatever it is they use everywhere
else in the world. But I found an interesting site in Durham as such:
http://www.dur.ac.uk/botanic.garden/

Cheerio (I'm bilingual),

Charles

Harold wrote:
What are the low winter temperatures down in the Durham area? Am
trying to determine what plants that grow down there might stand a
chance up here on the Cape....there is a constant discussion as to
whetheer we are zone 7 or zone 6....on the odd times our low for the
winter drops down to zero.......Harold