My Huldine has been in the ground for 3 years and it's already a monster. It would take over a rose of that size.

It's a very pretty rose.
http://www.rose-gardening-made-easy.com/westerland-rose.html

I have heard from other people that John Huxtable is a reliable white clematis. It will get about as tall as your rose, and should be prune each year. It is moderately vigorous and goes well with climbing roses (according to MT).
http://www.clematis.hull.ac.uk/new-clemdetail.cfm?dbkey=448

Blue and orange is great color combos. I think the color of Blue Angle would work with the rose. It's vigorous, but would play nice. The color is a light blue (ya, I know it's really a purple)
http://www.clematis.hull.ac.uk/new-clemdetail.cfm?dbkey=88

How about Etoille Violet?

The OP doesn't want purple.

Try 'Prince Charles'

Etoille Violet is a good clematis, it will be a bigger than your rose, and is considered vigorous. It's a nice deeper purple in my garden.

I'm trying to create a privacy screen with a trellis that my DH built that is 20 ft long and 6 ft tall. I have some planted already that will help cover that eventually. I have William Baffin on one side paired with a Crystal Fountain clematis and Dr Ruppel. Crystal Fountain is more vigorous for me than the good ol' Doctor. I was hoping to find a clem to pair with Westerland and I do have Franziska Maria planted about a foot away but she's a loser for me in the growth dept! This is her 4th season in my garden and she's only 3 ft tall! I have whacked her till heck won't have it but nada so she's getting shovel pruned either this year or next.
So, I need one that's vigorous enough to cover up the 6 ft tall and I don't worry too much about it growing onto Westerland.

Here's a pic of the situation. You can see Westerland on the left of the trellis.

{{gwi:604968}}

Do you want another Type II so they all prune the same or do you want a larger, more vigorous type III which will likely outgrow the six feet and cascade back down or over?

A more vigorous type III that will outgrow the six feet and cascade back down or over! :)

How about a reddish one? Niobe (not that vigorous for me),Keremesina, Carmencita, Ernest Markham?

My type 3s are a little later than the roses, except Hagley Hybrid, which just started blooming 2 days ago, while the pink centefolia near it is barely opening its numerous buds.

My Westerland didn't make it thru the Winter, but I have hopes that I will see some green before the year is over. I hope it was own root, as I already have a Dr Huey. I don't plant any more clems in that area because a humongeous Goldflame Lonicera has already strangled my first Atragene, Markham's Pink.

I think Price Charles would look pretty with Westerland but it really depends on what color you want to go with it.
It is similar in color to that salvia? nepeta? you have in front.

Here is a link that might be useful: Prince Charles

There are several others in similar colors if you can't find Price Charles but like that color combo.

Perle d'Azure, Betty Corning (smaller flowers, fragrant but a rampant grower will need more training) Blue Angel

Here is a link that might be useful: Blue Angel

Well, I do have Ernest Markham already growing on Westerland's right side but he's only one year old so still has to show his stuff in a couple years.

The paler colors of Perle d'Azure might look nice, or even the Betty Corning.

Thanks all for the suggestions! :) Westerland is such a different color that it's hard to pair colors other than purples lol.

Did you make a selection yet?

Not really. I'm still leaning towards Huldine because I've heard so much about how vigorous he is and what a great bloomer.
I have a Henryi that was originally planted to climb up Westerland, but he's a loser. This is his 3rd full year and he hasn't grown an inch in all that time dispite all my whacking back.
I thought I would replace him with a better White bloomer.
I know for one thing that I don't want another group 2 clem.
Ernest Markham is planted on Westerland's other side but has his own trellis to climb on.
EM hasn't impressed me either.
This will be EM's 3rd year and I have yet to see a bloom!
But, I am a patient gardener :)

I kind of like the paler lavender look too. So, I'm not sure what I'll get but I know I'll buy it from either Joy Creek or Silver Star Vinery.
I haven't bought from SSV yet but I've heard they are the best.
Joy Creek's clem have totally impressed me so far. Awesome clems!
I have a Sweet Autumn from them that was just planted last year and is already 10 ft tall this year! And really bushing out with no help from me except I cut to 6 inches in early spring.

Huldine will get enormous. As I said, I have a 3 year old plant already a monster. I have it on an 8 foot section of fence, which is too small. I will be moving it later in the season. Of course, it is your garden and you should do what you want :).

Maria Cornelia is similar to Huldine. It's a newer Viticella, white, but doesn't get as tall, 8-10 feet, whereas Huldine will reach 14' or up to 19' according to CoTW. I have seen photos of Maria Cornelia in people's gardens, the plant was full of flowers, which is the reason I bought it. I got mine from Brushwood, but they are currently out of stock.

http://www.clematis.hull.ac.uk/new-clemdetail.cfm?dbkey=3288

I share everyone's concern about Huldine. I have mine growing up a small crabapple, and I've begun to worry about it swamping a TREE! The crabapple is probably 20' tall and Huldine reached the top last year. I had the idea to grow a few long shoots up the tree to add color after it bloomed, but this year I've noticed that a lot more shoots are coming up and I'm afraid they may be more than the tree can handle. I think your Westerland would have trouble unless you carefully trained the Huldine around it. It's a big and vigorous clematis. You'd certainly get privacy, though!

I've got Huldine up a purple leaf plum tree that is mature. She is only two seasons old and already well up into the tree.

Ok, ok lol I guess Huldine would become too big lol!
How about either Etoille Violette or that Betty Corning? I know EV is purple but sounds very hardy for this area and is a group 3.

I second the recommendations for Perle d'Azur and Etoile Violette (for large-flowered varieties) and Betty Corning (for smaller). BC will give you quite a different look in that spot, a nice contrast. As for color, I think it would make a perfect foil for the Westerland (and the Ernest Markham). For both of those reasons, I'd favor going with BC. It's vigorous, but takes well to shaping. Just my $.02 Gary

I like the idea of Betty Corning, but I'm just afraid she'll overwhelm the Westerland Rose. It would be a nice contrast and a different look, as all my other clems are large flowered.
I'll check on Perle d'Azur.
I did go down to my local nursery to see if they had either BC or EV but nada. So, I'll have to order from online.
Thanks all for the recommendations! I've got some great ideas to think about. I'm tired of loser clems that are in their 4th year and still sleeping!

I have a lot of trellis to cover for the privacy screen I'm trying to create and losers don't accomplish what I'm trying to do lol!

Betty Corning reaches 9' on my trellis and then tumbles back down almost to the ground again. She spreads out 9' too and she also sends vines in all directions. I have to clip and tie them down or cut them off.

Etiole Violette reaches 7' and then tumbles back down but only about half way.

Prince Charles reaches 7' but doesn't really tumble back down much at all. It is smaller than my other Type IIIs.

Kenstar, do you have to cut back that rose each year? Will it reach it's maximum size?

There is a group of very nice clematis, hardy and good bloomers, not as wild as the viticellas. It's the Kivistik collection. I think Silmakavi would look really nice with your rose.

http://hummingbirdfarm.net/kivistik_clematis.htm

I hope the rose will reach it's maximum size, but here in my zone it may not. I do have to cut back some in spring, but I do protect the rose with a mound of leaves, and soil or peat moss and I also burlap the rose.

I would think the kivistik clems would be too short as I am trying to create privacy.

Kentstar, I have a 20-year old mature 'Betty Corning' here in central Illinois. I can tell you from personal experience that BC will devour Westerland; mine is a stand-alone shrub and is so huge that little wrens build nests in it in the spring. I recently purchased a 7-ft. hoop obelisk in the hopes of keeping it from swamping 'Rosarium Ueterusum' on a neighboring trellis, which seems to have helped tame it somewhat. It's a very robust grower and is a specimen plant at the entrance of one of my rose gardens.
-terry

I think I'll leave out Betty Corning then thanks terryjean!
I'm still considering Etoille Violet though.

My vote goes to Maria Cornelia if you want white. The plant has been vigorous for me and the flowers are a little smaller than Huldine and blooms a long time.