Hardiness Zone Map for the UK and Europe
Applying zone references
Plant encyclopedias may refer simply, for example, to "Zone 6," which generally means that the plant is hardy to that zone (and will endure winters there), and generally can withstand all the warmer zones below. More detailed information may indicate a range of zones (i.e., "Zones 4-9"), which means the plant will only grow in those zones, and will not tolerate the colder and warmer extremes outside them. But zones are only a guide. You may find microclimates that allow you to grow more than the books say you can; by the same token, you may find to your dismay that some precious plant -- one that's "supposed" to be hardy in your zone -- finds its way to plant heaven instead.
These are the hardiness zones (lowest winter temperatures)
likely to be encountered in Europe:

Zone 5: -29 to -23 C (-20 to -10 F)
Zone 6: -23 to -18 C (-10 to 0 F)
Zone 7: -18 to -12 C (0 to 10 F)
Zone 8: -12 to -7 C (10 to 20 F)
Zone 9: -7 to -1 C (20 to 30 F)
Zone 10: -1 to 4 C (30 to 40 F)
Plants surviving in my beds should be hardy in Zone 8 and above,
although there are some stated to be hardy down to Zone 5.

For a more detailed map, click here