I was not familiar with Violet Charm so I looked it up on Clematis on the web. It says it has red anthers, so it may not be Violet Charm. Multi blue has white anthers. Some doubles do produce single flowers especially on new wood. It is very pretty what ever it is. I love the color.

Here is a link that might be useful: Violet charm

I am not one of the experts here, but he looks like HF Young. I bought him this year and I couldn't be happier. His growth has been vigorous and I love the lavendary-blue shade of the blooms.

Carolyn

Here is a link that might be useful: HF Young

I was also thinking that it may be a multi-blue too. The color is right on for it. The flowers are pretty big though. It does look a lot like HF Young Carolyn! It doesn't have the right color anthers for Violet Charm. Whatever it is, the color is incredible. Should I assume it is a group II for pruning?
Adrienne

I would guess HF Young also but there are so many of those lighter blueish purple type IIs that it could be any one of a multitude of clematis. I would assume it is a type II clematis, but remember to treat it as a type III for at least the first year of pruning to help get it established and to increase the number of vines coming out of the crown.

I was also going to say HF Young because I did buy HF Young from Home Depot this year and it does look like your picture. Your flower is a very beautiful clear color.

I've NEVER had Multi-Blue produce a single bloom like that. The centers are always "fluffy" no matter the season. Multi-Blue is darker than that too.

I'm voting for HF Young.

It is a group II but should be hard pruned the first couple years to get off to a better start.