I have had very good luck with New Dawn----Viking Queen ----Compassion----Albertine (once-blooming rambler)
My zone is 6b7 ----I'm sure you will hear from people in your zone who will be able to give you more information.

welcome to the rose Forum----It is a great place to find out about roses from nice people--

Also check the Antique rose Forum.

good Luck,

Florence

I will cut & paste what a representative of Palatine Roses wrote me just the other day about a few of their newer climbers:

"Laguna is the most fragrant climber in our line up. The hot pink old fashion quarter bloom is very stunning. However, you must know that it grows very vigorous and almost like a rambler it will need to be tied up regularly (the exact words of my father  it is all over the place). Another rose you may consider is Rosanna. We feel that it is stunning and showy. It has a globular pink bloom. It is more civilized and 10 ft tall. Rosanna has the highest tolerance to both mildew and black spot. Laguna is slightly more susceptible to mildew. Both will be OK for your Zone (zone 5a)".

I have no idea on how thorny they are. Jasmina also looks very nice (to me). Their rootstock is multiflora, which is good for our winters. I also hear great things about Fourth of July. I hope lots of people from cold zones post, as I am interested as well.
:0) Phyl

"no winter protection (if possible) in my zone 5 (Iowa), easy to grow / prune, resistent to mildew, thornless, prefer smaller or no canes"

no canes? That means no rose. Can't imagine what you mean by that, but if you are in Iowa, look at the Buck roses. They were bread by Dr Buck in Iowa, specifically to survive in your climate. They would be a good start. that said, I can't think of any w/out thorns. Climbing James Galway is fairly thornless and it's a climber and disease resistant - I don't know how it will do in your climate though. The more common thornless climbers like the Bourbon roses, are not all that disease resistant.

I don't have this one yet but how about Cornelia? No pruning, nearly thornless and shade tolerant. HMF says hardy from zone 5.

Here is a link that might be useful: Cornelia

John Davis-Explorer Rose

It is really more of a large shrub/rambling rose than a climber, but its growth habit will lend itself very well to growing and training outwards along a fence.

-requiring no winter protection (if possible): It is and will be hardy to the tips in your zone 5 (Iowa) garden

-easy to grow / prune: It is a very vigorous rose when grafted and easily goes own-root if planted deep. It is less vigorous for the first 3-4 years when grown on its own-roots as opposed to a grafted specimen.

-resistent to mildew: Yes, very resistant, although it can mildew when grown near house walls with not enough air circulation and dry soil at the foundation. This will not be a problem on a fence. This rose likes lots of water and good soil. Make sure it gets both.

-thornless: Has some thorns, but not many and they are not large.

John Davis is also a very heavy bloomer and once established and well cultivated, blooms pretty much non-stop through the summer and up to late fall.

Good luck.

Of course I don't know, but I'll be trying a Constance Spry, and probably also Baltimore Belle.

You might also look at ramblers rather than climbers. I have a couple and some on order. I seem to lean toward the own root ramblers rather than the climbers.

My strongest suggestion would be New Dawn. Make sure it is New Dawn and not a sport or seed of this rose. New Dawn, though prickly, and yes, she loves to reach out and touch someone, it is a clean rose, very strong and is a blooming fool.

Another I have is Queen of the Prairies. This found rose is probably one of the best, or at least even with New Dawn. It has fewer prickers and will bloom better as it establishes. I've had no winter kill with this rose and it is at least as disease resistant as New Dawn or better. I haven't sprayed this rose yet. It does want time and is from I could find out a long lived rose. I don't have any good pictures of it yet but I will be getting some. It's a pink flower with a lot of petals and is quite fragrant. It's also hard to find so you might try Vintage or Roses Unlimited. Check out www.helpmefind.com as well.

Last but not least, and not classed as a climber but diffinately large enough to be considered a climber is Sally Holmes. This is one very large shrub that can get to be nearly 10 feet tall. It has a few prickles, but it's not the killer that New Dawn can be. It is a five petal white with flesh colored buds and is absolutely stunning. It has extremely good disease resistance.

Others have given you quite a number or really good ideas. Check into each one carefully and ask questions about the ones that make it to the final 5 or 10.

HMF says Reine des Violettes can get up to 8 feet tall. Thornless.

I love my John Cabot, but it isn't thornless. It has rather nasty prickly thorns but it is winter hardy (to the tips) and gets large quickly on its own roots for me. I have a new Reine des Violettes that is thornless and does grow fairly tall (was five feet this fall) but this is its first winter so I don't know how well it will do up here. I'm planning to grow RdV as a large bush. I'm trying Quadra from Palatine this spring and possibly Chianti.

Autum Sunset grew ridiculously easy here in DC and seemed to come through the snows just fine.

I have a Reines des Violettes from Malcolm Manners. Therefore, I would consider mine the real thing. I love it. Mine has some thorns (or are they technically "prickles"?), although not a lot of them at this point. (Mine is still young). I wouldn't consider it thornless.

I've never seen a rose that is totally thornless, despite claims to that effect. I've always found a few, or rather, they found me.

Sandy