Most of the Austins don't casade down. Sea Foam is a good cascader and there are others. Try Vintage Gardens for your Giganteas.

I've had luck with polyanthas on walls. Also look into some of the ground covers and miniature climbers.

Gertrude Jekyll recommended 'Lamarque' for walls in the Riviera, and I think that is a wonderful choice. It just drips with foliage and flowers, has very long flexible canes, and blooms rather constantly.

Another fabulous droopy rose is Souv de Mme Leonie Viennot. In our climate (Sacramento), it only blooms once, with scattered repeat, but what a show when it does. I see a lot of gigantea in this rose, in the shape of its buds, foliage and flowers.

People say there's gigantea in Fortune's Double Yellow, but the foliage and buds aren't as pointed.

I think that any of the flexible ramblers could achieve the effect that you'd like - roses like Alberic Barbier, for example.

R. brunnonii (Himalayan Musk) also has the growth habit that you're looking for, and the great benefit of fabulous hips in fall and winter. I've never grown Paul's Himalayan musk, only the species, but it may be another choice.

So far as I know, Lijiang Road is not in commerce in North America. The Sacramento cemetery has a climbing China, Phillips and Rix Pink China Climber, that has a similar growth habit, and was collected by them on the same trip to China (hence the name), but it's not in commerce. We try to sell it at our Open Garden.

I think that the look you are going for will be fabulous. Let us know what you pick, and take pictures!
Anita

I am also in Sunset Z24 CA, and we have found that Souv. de Mme. Leonie Viennot will not bloom here at all.
It's terrific in Sacramento, and beyond spectacular in TX, but a bust in Ventura Co.
A 16-y-O one in Santa Barbara does bloom, and gets scattered late Fall repeat, but I'm not up to waiting a decade for bloom to happen.

Jeri

Ladybanks. Flexible canes and no thorns! It is a once-bloomer but is evergreen most of the year for me.

AND in Sunset24, the double yellow banksia will scatter bloom through the season, hesitating only in the hottest weather.

Jeri

Another big, weepy rose to consider is Peggy Martin (if you want pink).
Here's a link to a beautiful pic posted last year on the Gallery:
http://forums2.gardenweb.com/forums/load/rosesant/gal0406071917277.html
I'm not sure if it is fragrant if that is important to you and the pictures I've seen of it are of roses grown in the south. Not sure how it fares in CA.

Not all roses have the hydrodynamics inside of them to force nutrients to 'flow' downhill. Thus the broad vase shape of many roses.
On many of my biggest roses, I see them throwing long canes that start off vertical and then they start to be pulled by gravity. When that happens, often the terminal end will die off and the rose will favor the leaf axils that are at the higher part of that cane and those are where the new, favored lateral will emerge.

Thanks for your help everybody. I will take all your suggestions into consideration. It's so hard to choose, but luckily I have a lot of wall space to cover.

Jeri: Do you know if the reason why Souv de Mme Leonie Viennot doesn't bloom is because we don't get enough heat in our zone?

Huttnem: I currently have a yellow Lady Banks that is languishing somewhat in the partial shade it gets. Maybe I should move it...It does do well in my area though.

Ann: I have not personally seen that in roses, but I have in other plants. I have seen a Bell of Portugal covered in bloomgs drooping down from a tree, which is one reason why I like gigantea hybrids so much. Maybe the vigor of the plant decreases the effect of gravity and counter-intuitive nutrient flow. Do you notice if the canes that bend downward have more blooms? I think some people recommend bending down limbs on fruit trees to decrease vigor and promote development of flower buds.

We had Pauls Himalayan Musk planted near the wall before and it was rambling over it, my DH was joking that it looks like some giant spider was trying to crawl over the wall. But it gets HUGE, so I don't know if that would work out so well. Also it has rather short flowering season - lovely when it does, but it lasts for 2 weeks only over here.

I've seen "Susan Louise" a R. gigantea hybrid that was not quite cascading but it was trailing off and down a sloping ground, trailing off the low wall that it was meant to grow upon. It is a lovely rose, with large Tea shaped blooms of pink and cream. Re-bloom is very good, and here it blooms through every season in the S.F. Bay area, where c. 95% of Evergreen roses bloom fully only through 3 seasons.
I've seen several "Alberic Barbier" growing down a hill slope and the lowest canes on the slope were blooming as well as the canes that had a higher elevation. In San Francisco during the 1900's a man trained several Rambler plants of one cultivar, to form the numbers of each year, 1928 etc... and that would require some cascading.
I too love "Lamarque" and especially the California form that has larger blooms. However the "Lamarque" that I was training a couple of weeks ago had thicker basal canes that are not as flexible as the basal canes of "Crepescule", that I'm in the process of espaliering against a wooden fence.
Theory: I read an article a few years ago that mentioned that rosebushes naturally produce a hormone at the top of each blooming cane-tip (I wish I had written down the name of that hormone) which has the trait of preventing (or trying to prevent) roses further below that height to bloom. It sounds like a Darwinian trait of survival of a dominant ...thingie, to me. This is why pegging a rose cane works so well and increases bloom upon a cane that was drawn so its tip is below its normal height. This gives me hope that it might be possible to cascade a rosebush. I get very excited about doing uncommonly done things with rosebushes.
I'd give it a try with 1-3 different types of rosebushes and see how each perform.
I would try and cascade these roses:
- a remontant purple rambler-bred rose that roguevalleyroses.com is selling, that re-blooms called "Perrenial Blue".
or
"Crepescule" a lovely apricot Tea-Noisette rose with pretty foliage, that I've found easy to train.
or
- "Susan Louise" will grow to be c. 25 feet long, but you try draping it and the other two, in festoons, I think that is the word. I've seen photographs of this being done, but from the top of a pillar to another pillar. 3 festoons are below, on their sides, I couldn't print them as they should be. The lowest part is towards the ground.
( (
( Festooning, might work better because each rosebush would not extend so low, which might aid growth.

How long is the wall?
I'd let the rosebushes grow upwards 5-6 feet, the direction they are used to, before training them downwards. I'd train them in winter when they are less "awake".
Please post when you decide on a rose or two.
Luxrosa