I have seen the same incorrect zone information printed in books - both zone 6 and zone 4 are sheer nonsense for this species.

A poster on the Far North forum has found it to be hardy in zone 0B (northern Manitoba) - see her account towards the bottom of the attached thread.

Here is a link that might be useful: Far North thread

Well, thanks very much! I feel quite relieved, as I really want this plant - it looks lovely. It makes me wonder though what other things are "zoned" incorrectly, as that thread indicates.

Anna

Believe me - the zone ratings for a great number of species are inaccurate with respect to the minimum (coldest) zone. It's a good idea to simply ask for other people's experiences with a certain species (as you've done in this case). Also, keep in mind that with less-common species, you might be one of the first actually trying it in a colder zone - that is, if no one has tried it below zone 4, then why should zone 4 be assumed to be the lowest zone?

I think where the book was written and published can also come into play on occasion. For example, a book written in the U.K. may list some plants that are hardy to zone 3, but as most of the United Kingdom is zone 8 or warmer, what do they care if they mistakenly list a zone 2 plant as zone 5?

Yes, on occasion - though I have British books that are quite accurate on zone ratings (perhaps because the author has a sense of the natural range of the species and/or a broad knowledge base and/or puts the effort into research). And I've seen Canadian publications (books and magazines) make the same errors - and if the authors and/or editors don't know better from their own experience, they should at least do the research, rather than just copy the zone ratings that were published in the books that predated their own. (Whew, will I ever give this a rest, LOL!)

Lori, you should write your own plant book and use your own experiences with all the beautiful plants that you grow in your garden.

Seriously!

Sharon

Provide strong support for this vigourous monster...She will grow up and over your roof. Definately hardy on the southshore...

WD420

Hi - I've grown this clematis in Denver, CO - zone 4/5. It's very hardy and invasive; be prepared to find it everywhere, and as whitedove sez, give it somethong sturdy to grow on. Despite its thugish tendencies, it is quite lovely. J

Ah that sounds great! I need it to cover an archway and that seems like just the ticket. Will it need lots of sun?

Thanks again - you are all so helpful!

Anna