Just like Lays potato chips and not being able to eat just one, I could and never would recommend only one type of clematis. There are way too many great ones out there to ever be able to pick just one and each garden is different so what might do well in one garden might not do well in another. I might like one for its bloom lenght, one for its fragrance, one for its care free manner in the garden, one for its flower shape--way to many to choose one in my estimation.

Favorites for me are the ones in bloom :-)

I've linked to a list of clematis for beginners.
It's a nice place to start, and it includes more than just the viticellas, but as with all clematis, it largely depends on its conditions, care and the strength of the plant, so nothing is really foolproof. Well, maybe Sweet Autumn, but that is almost a weed.

There are Montanas and Tanguticas on the list; Montanas are out, or there might be one that is ok, but I forgot which one. The Tanguticas are very sensitive to late frosts, so avoid those too.

Here is a link that might be useful: Clematis for Beginners

Daniel Deronda is my best performer, bar none.

Venosa Violacea. Her loveliness cannot be captured on camera. Mine has been blooming nonstop for over two weeks and still going strong. She is climbing over a Ballerina rose and some pink delphiniums and Japanese Iris.

If I could only grow one clematis, this would be the one.

Mary

Thank you for the link, Janet. GardenWeb is addictive because its members share such great stuff.

I agree with whatever is blooming,however, I guess if I had to pick one it would be Betty Corning.She is just a second year plant and has been covered in blooms for at least 3 weeks.I thought she was done for the season but just noticed a lot of buds. I like the pretty nodding flowers and have been told it is supposed to be fragrant but mine isn't. At least I cannot detect anything!!!!!

Venosa violacea has my favorite flowers.

If I could only pick one, I guess I might pick Princess Diana for its graceful beauty, trouble-free vigor, and prolific bloom.

But then again...I might actually have to choose a large-flowered type - they are the classic clem, aren't they?

So, of large-flowered, I would pick my new fave, Warsaw Nike. The color is stupendous. It is also very vigorous and floriferous so far in my garden. Honorable mention to my first clem, H.F. Young. It is the perfect delft blue with creamy contrasting center, and so much more bloom than what the descriptions lead you to expect. Takes a while to mature, though.

I'm excited to see that two of my babies in the nursery are mentioned here - Venosa violacea and Princess Diana! These are ones I got from Bluestone.

The only mature plant I have is Piilu in a container. So I guess for now it's my favorite! LOL!

I buy clematis (and come to think of it, most plants) based on how pretty the plant is. I don't seem to have the foresight to think of where I'm going to plant it or what it would look good with. Not much artistic abilities on my part. But fortunately, I do seem to be able to grow things. Oh, and I also buy based on "is it a bargain?". Hence the two blueberrie bushes sitting in my driveway, because it turns out that Colorado soil is too alkaline for them. So I need to get some large containers for them (and more potting soil). So much for the bargain!