Jayne wrote:

Sorry - I didn't say. I'm in South Gloucestershire.
Last year's summer hanging baskets lasted until the first week in December.
We are in an open area rather than a built up one - just open farmland
behind the house, but fairly high up.

Jayne

Looking at past records may give you *some* idea.. of what to expect.

As you say your high up you may be a little more exposed that in a
sheltered lower site, but at least you aren't in a frost pocket at the
base of a hill;-)

sites like Wunderground.com and the Met Office
http://www.met-office.gov.uk/
allow you to view the weather records for your area.
//
Jim