[.ca] Gardener's Directory of Shrubs & Climbers: A practical ... (ISBN 1844763935)

Very confusing:
A nice book to look at - lots of colourful pictures and brief descriptions - but its credibility is suspect based on the extremely confusing zone ratings. The book is printed in the UK, but it shows a US hardiness zone map. However, the zones listed for most of the plants make no sense. For instance, most plants are rated at zone 7 or higher. That is somewhere in the southern US, yet many of the plants so listed do quite well in my garden in Canada. In addition to the zones is a 3 star hardiness rating with 1 star being "half hardy (down to 0C)" and 3 stars being "fully hardy (down to -15C)". Thus, a plant such as Parthenocissus quinquefolia (Virginia creeper) is given 3 stars - which makes sense - but states "zone: Min. 7". Very confusing. All other books I look at rate this plant as US Zone 3. Another example: Buxus sempervirens is listed as Zones 7-8, yet grows much farther north and most sources suggest zone 5 or even colder. I have looked through the book but have found no explanation for these discrepancies. If you live in the southern US where these hardiness zones probably don't matter, then the book is probably good but if you are north of the Mason-Dixon line, then forget it. In addition, a table of comparisons would really have made the book more useful. For me there are many better books out there for the money.