I did some creative googling for you (you helped me procrastinate doing some housework, so thank you!), and it looks like durandii to me. Look it up and see if you think I'm right?

Here's one of the images that sold me:

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It definitely looks like it can be an integrifolia hybrid or even some sort of viticella hybrid. One way to rule the viticella hybrid out is to see if it clings on its own or if it just weaves itself in and out of the trellis you have it on. The integrifolias generally are not self clinging whereas any viticella hybrid would be. I can't tell from the photo anything about its clinging tendencies.

I have never seen Durandii look as blue as the color in either the OPs picture or in the picture Violetta posted. Mine is a darker purple in color and even in my intense sun, it has never faded to the color in either picture. Then again soil conditions could affect the color of your clematis' sepals. Another option might be Blue Boy or Eriostemon which are other hybrids. Whatever it is, it is one gorgeous clematis.

Cupshaped roses, is this a clematis you planted or one you inherited at the house you live in? It doesn't look anything like the texensis varieties that I am aware of but then living in Denmark, you may have access to ones that I have never seen before!

Looks like an Integrifolia to me too.

My Durandii isn't that blue either.

It is gorgeous!

I was really surprised about Violetta suggestion it could be Clematis Durandii. I do grow that clematis 2 other places in may garden and they do not do that well here. This clematis does much better!! I must say that they flowers look very much like Durandii, so I went out to take a look at plants today and compared them ... they are not the same (leaves are different. Both do however not "cling". I do grow a blue Integrafolia clematis, It is only about 2.5 feet tall.

I do not not know where I got the idea it could be a texensis variety ...perhaps the bellshaped flowers? I did however check your leads that it could be a integrafolia hybrids ( I thought most integrafolia type clematis was 2-3 feet tall) this is about 8 feet tall. I looked through different websites looking for integrafolia hybrids and I found a match!!!!!:

It is probably either Blue Boy (Clematis 'Blue Boy' is a C. viticella x C. integrifolia hybrid raised in Canada by Dr Skinner in 1947):

http://www.roselandhouse.co.uk/clematis/clematis%20blue%20boy.htm

Or it could be Clematis "Hendersonii":

In 1835 J.A. Henderson crossbred Clematis integrifolia with Clematis viticella producing Clematis x diversifolia 'Hendersonii' - a beautiful perennial clematis, semi-herbaceous in habit, the oldest hybrid in cultivation. It has deep bluish-purple bell-shaped slightly nodding flowers with yellow stamens. Free flowering from June to September. It's an excellent companion plant for deciduous and coniferous shrubs.

http://www.clematis.com.pl/wms/wmsg.php/854173.html

I got the Clematis from a Lady 15 or 16 years ago. She did not know the name of it. I grow it against a fine rebar mesh against a wall:the Clematis in the middle of the picture, The other one in the front is clematis viticella "Etoille Violette":

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I had no idea hybrids between integrafolia and viticela excisted. It is most likely Clematis "Hendersonii" since that cultivar seems to be available here in Denmark.

Thank for pointing me in the right direction. (I hope violetta finished her housework!). See picture in this link:

Here is a link that might be useful: {{gwi:625544}}

Okay, I was wrong, but I'm glad you found the answer!

WOW, I just love your mystery clematis. It's just the exact color I want in a clematis. I sure wish I could find one of those locally, because we have very little clematis nurseries that will ship to Canada.

Glad to have been of help cupshaped roses. Knowing the height of the plant would have also ruled out Durandii. I have seen some pretty tall specimens of Blue Boy but not as tall as your unknown one. According to COTW, Hendersonii can get 1.5 to 3 meters tall (4.9 to 9.8 feet), so it very probably is that variety. Then again, they also list Blue Boy as getting as tall as Hendersonii. Either one are great plants. Yours truly is a show stopper!

Here is a link that might be useful: COTW picture of Hendersoni

I know it's too late to order this year, but if anyone has seen this clematis hendersonii for sale and available in Canada, I would appreciate an e-mail. I can't stop coming back to look at this one. I love it. Will be looking for this one when new lists become available.

Magnus Johnson compared the 3 integrifolia x viticella hybrids ('Blue Boy', 'Eriostemon' and 'Hendersonii') in an article submitted to the International Clematis Society's newsletter vol 4 Winter 1987.

The article details some of the history of hybrids(going back to circa 1830) but more importantly tabulates the distinctions. From this table there are very subtle differences and the photographed clem could, perhaps, be any of the three, or perhaps another integrifolia/viticella cross.

On reading the distinctions it would appear that 'Blue Boy' has more ovate/near globular flower buds wheareas Eriostemon and Hendersoni are short conical and long conical respectively. 'Blue Boy' would also appear to exhibit a greater number of simple leaves, particularly near the base of the plant.