Looking for Tallest Buddleia. Suggestions?

I need a tall Butterfly Bush to tower over an established stand of red Knockout Roses. I've seen 12' ones, which would be ideal, but, when I checked max height on White Profusion, I find that it should only reach five or six feet, which won't give the effect I want.

Can anyone suggest taller varieties/cultivars?

Thanks for your input!

http://davesgarden.com/guides/pf/go/2332/

That one gets bigger.

I don't know, though. Looking at the pictures, it does look a little spindly. This one has a lot of pretty good comments if you are not stuck on white.
http://davesgarden.com/guides/pf/go/49898/

I have the Buddleja asiatica and it does get very tall, plus it grows very fast so it'll get 10 ft or so in one season. Unfortunately all that fast growth means if you have a big windstorm it'll get knocked over, that's what happened to mine this past winter (wind gusts were probably ~50 mph during the storm that blew it down). It's regrowing nicely, they're just like any other Buddleja in that they're very hard to kill, but if you want something that's going to be a permanent screen in a windy area this is probably not the right plant (nor are any of the other Buddlejas in my opinion) B. asiatica also has wonderfully fragrant flowers in late winter, although since you're on the colder end of its range if it gets a lot of frost damage I'm not sure how it'll bloom--I definitely had better blooming this past winter than I did the winter before when we had a really unusual cold snap (a week of nighttime lows in the high teens/low 20's)

You might also reconsider the davidii cultivars, maybe even your White Profusion--I'm not sure who put the heights in Plant Files, but I think 6 ft or so is the height they'll get to in 1 season if they die back and resprout from the base as they do in many colder zones, or if you live in a warmer area and keep them well pruned. In warmer zones where they don't die back, I think most of them can get considerably taller than what's listed in PF. I've seen ones that were literally 20 ft tall trees around here, so I think if you don't prune it, yours will get to be the height you want.

Thanks, Pamela. The Asian white does seem spare, and it only has one flush of bloom on year-old wood, rather than the continuous bloom of the davidii hybrids. We already have a Purple Emperor, which is close to the color of Black Knight, so I was hoping to bring in another color. I was hoping to find a white to contrast with the red rose and not get too color-confusing with the mixed cannas next to it. I haven't seen a pink, but, with so many attempts at red, I woul have thought that would have been a byproduct.........

These types of shrubs look best if being deadheaded regularly, otherwise, they will be unkempt looking with the brown spent flowers....

Likes ecrane2 has mentioned, these do get killed back in our zone, so the maximum height would be a challenge to attain?

I trim mine back every year in late winter, and they bounced back more vigorously than the last.

ecrane -- You're right, I think the asiatica has many drawbacks for this area.

The very tall davidiis you've seen are white? I was sure I had seen them taller, but, since the on line listings contradicted that, I was hesitant.

Have you considered crape myrtles? They have some pretty blooms that bloom all summer. This website shows lots of different varieties and sizes.
http://www.clemson.edu/crepemyrtle/

I've seen all sorts of colors of huge buddleias out here, I really think if you don't prune them most of them will get really big unless you bought one of the newer cultivars that was bred to be dwarf. I remember being shocked when I first moved out here at how huge the buddleias were, I never had any idea they could grow that tall because I was coming from zone 6 where they die back every winter and usually only got 4-6 ft the following year.

Pamela -- yes, we have a white crape myrtle on the other side, but we don't want shade in this area, and buddleia lets plenty of light through.

Lily -- I'm used to deadheading buddleias. It will be fairly protected, inside a 6' privacy fence. Many plants have done well there, when they are normally rated for one zone warmer. Besides, the tallest buddleia I've ever seen was in z5!

Ok, now I'm finding some listings that show 6-8', which, given what is being written here, would mean 8'++ for us.

So, does anyone have experience with the different white hybrids, i.e., which would give the most flowers?

I've found the names:

White Bouquet
White Profusion
Snowbank