Clematis groups?

I understand there are different groups for Clematis species, based on their pruning needs. Here's an excerpt from a website that shows 12 groups:

1. The Evergreen group
2. The Alpina group
3. The Macropetala group
4. The Montana group
5. The Rockery group
6. The Early Large-Flowered group (aka Patens group?)
7. The Late Large-Flowered group (aka Jackmanii group?)
8. The Herbaceous group
9. The Viticella group
10. The Texensis group
11. The Orientalis group
12. The Late Mixed group

I'm wondering if these groups are standard everywhere? And are there any other special characteristics for Clematis that - if we added them to the PDB - would make it easier to add cultivar entries? Comments, opinions and suggestions are VERY welcome :)

12!!!!!! I am corn~fused enough with the standard 3!!!!! YEEK!

I only have 3 clematis and I think that I remember reading that different groups have to be treated differently in order to thrive. Different methods of pruning.

Would sure like to know how to tell the difference.

Well, I've been doing a bit more research, since this thread didn't seem to be generating much response. I just learned that the RHS is working on the Clematis Register and Checklist, due out in July.

At that time we'll be able to use this comprehensive body of work as the basis for creating classification checklists for Clematis entries in the PDB. Which should help all of us be better Clematis growers, as more information can be added to each cultivar and species in our database :)

Good for you Go_vols. I just found this thread and will be watching it with interest. Now that I have all these new clematis I want to do the right kind of trimming for the new babies.

Seems like different groups have diffenet leaves. I know some of mine have big leaves and not alot of them. and some have zillions of leaves and they are tiny. ~~ But. which is the best placement for them. N,S,E

I bought 2 Bush Clematis from Jackson & Perkins this month, they were up about 3 inches and the frost got them. I sure hope they will come back & grow. The other climbing ones were nipped too.

This message was edited Monday, May 27th 11:07 PM

I love my clematis. I have 5 or 6 different kinds. I can not remember which one to prune back--so I don't. Maybe my wall of Cematis would look better than it does if I knew which one to do what to--na I don't have the time and they look just fine to me. Just keep the roots shaded from the hot sun and forget the rest!