Ahh, Roger, hard but true words! We are always seeking a simple solution to the complexities of life. I didn't realize that the Arnold Arboretum (a truly wonderful place to visit!) was behind the original Zones. Another factor we often forget, along with percipitation, is the strength of the sun. As far north as I garden, despite being a technical Zone 8, much like Vancouver, we are at the latitude of Calgary! Due to the mild climate, we only have about 2 weeks of hard frost, somethimes less, very wet Winters and very dark ones as well! Many South Africans grow happily, but do not bloom due to the lack of sun energy. In the end, Zones are nothing but a guideline and one must not only know his local conditions, but understand them as well! Jamie Vande Cologne Germany where the six-pack never caught on (we buy it by the 24 bottle case!) ----- Original Message ----- From: "Rodger Whitlock" <totototo@telus.net> To: <pbs@lists.ibiblio.org> Sent: Friday, October 28, 2005 7:05 AM Subject: Re: [pbs] Climate Zones. > On 27 Oct 05 at 17:23, Lee Poulsen wrote: > > > ...I have to hand it to the USDA for thinking of the single > > best parameter to use in creating the first Zone map and then > > making the map and seeing what the result was. > > The USDA zones were devised strictly, solely to gauge > hardiness of woody material: trees and shrubs. That's all. They > simply aren't applicable to other categories. IIRC, they were > invented at the Arnold Arboretum. Presumably they work not too > badly for their intended purpose -- in eastern North America, > that is! > > In particular, the hardiness of bulbs and perennials depends > on many other factors than just winter lows. > > And the hardiness zones are of very dubious worth in other > parts of the planet. They only keep going because Joe Sixpack > likes things reduced to a single number, no matter how > misleading it may be. > > > -- > Rodger Whitlock > Victoria, British Columbia, Canada > Maritime Zone 8, a cool Mediterranean climate > > on beautiful Vancouver Island > _______________________________________________ > pbs mailing list > pbs@lists.ibiblio.org > http://www.pacificbulbsociety.org/list.php >