I've never lived in one place long enough to see a rose take off, do well, then go downhill simply from age. In NJ, if a rose was prone to black spot, it usually died inside two years. If it didn't die, it generally went on to do well for years thereafter. I have seen roses planted in thin soil stop growing. In NJ I grew Champlain on four inches of clay soil atop about a foot of gravel and then subsoil. It pretty much stopped growing after the first year, but it bloomed faithfully for a decade. Similar conditions prevailed for Raubritter and Great Western. Actually, I sprayed bits of that bed with Roundup to kill bindweed and/or thistles in year three and Great Western never did fully recover. I lost very large and healthy instances of Mme Plantier and Dortmund to Roundup also. I had some albas that grew quickly, but sort of outgrew their space. Their blooming glory tapered off a bit as they got crowded. I'm pretty sure that careful early summer pruning would have restored them to their full glory, but I never did it. It seems to me that all the cases of decline in that garden could be traced to a known cause such as an observable disease, shade, encroachment/crowding, or bad chemicals. (I certainly do not mean to imply that it doesn't happen. Or that it had anything to do with my own gardening skill which I judge to be very limited - if not in theory then certainly in practice.)
Here, roses tend to die of drought or of freeze-thaw cycling. Established roses tend to be less prone to the problem. This last season I was more careful to deliver adequate water and fertilizer to all my roses, and I've seen a general upward trend in the health of every one. None has grown here long enough to produce a dead cane, none has required rejuvenation by heavy pruning. A few young roses have been crowded out by neighbors and want to inhabit new territory.
I think rootstock can play an important role in rose health and longevity. With two exceptions, every hybrid tea rose I've planted here on its own roots has died quickly. Amatsu Otone and Belle Epoque are the exceptions and after two full seasons in the garden, neither is yet knee-high. It's definitely not disease that keeps them from growing. And this year, it was not dryness either. I just think most HTs are not capable of growing quickly on their own roots. I've planted HTs from both VG and RVR, so I think it's more of a thing about the rose material than it is about the supplier.
Some floribundas, I think, might be better. Geisha certainly is not one of them. Sexy Rexy and Parfait might be. Maybe Kimono. City of Leeds seems pretty vigorous. Centennaire de Lourdes - given adequate moisture certainly is. Pink Parfait does a bit better than HTs, but not much. I've lost six Iceberg on their own roots here from two suppliers, so I'm not planning to grow Iceberg here for a while. By contrast, in its first season Europeana on multiflora rootstock has grown over two feet high and bloomed all summer long - and in the same area where Iceberg died. It's much more vigorous than any floribundas on their own roots. Certainly Rainbow Sorbet has proven vigorous on both multiflora and Dr Huey rootstock. Who knows how these grafted roses will be doing twenty years out, though.
I have had a few roses die at the very end of their first year - in late March or early April. Playboy set out an impressive flush of lovely purple foliage after a long warm stretch in Spring 2010. Then frost hit. And that was it. Much the same has happened to Don Juan on its own roots last spring. Interestingly, Don Juan on Dr Huey rootstock remained completely dormant through March and April looking totally dead. Then in May it perked up a little. Finally, when we got good rains in July it started growing vigorously. Much the same thing happened to an Ambridge Rose that was buried during construction. It emerged in July after the monsoons started. A very similar thing happened to Graham Thomas. On its own roots, it set foliage in March. Then late frost killed it. On Dr. Huey rootstock, by contrast, I have seen it wait for good weather. It's unexpected, but rootstock can play an important role in the the hardiness of a rose in places that have bouncy spring temperatures and late frosts.
The rule seems to be that hybrid tea roses need to be grown on other rootstocks. On their own roots perhaps they can survive if one is willing to go to great extremes to assure soil fertility - see also the regimen recommended by Roses Unlimited. Of course, if one lives where hot humid weather and blackspot will otherwise kill a hybrid tea rose, rootstock will make little difference to the outcome. Some of the exceptions are interesting. The large flowered climber Orfeo - which looks to me like a very long stemmed hybrid tea rose - arrived here as a band in spring of 2011. I was sure it was not going to survive. In fact, at one point it accidentally popped out of the ground in its first year and I noticed that it had about a cup's worth of roots that were about two inches long. I was sure it was a goner. But a year later it has two or three six ft canes and is growing vigorously. So here is a rose that is essentially a HT, and yet it seems to grow vigorously on its own roots. Good to know Lafter does, too. I've seen it growing at Antique Rose Emporium.
OGRs certainly can grow vigorously on their own roots. Mme Alfred Carriere has set the record here for first year growth, setting three or four six foot canes in its first year - another own-root rose from ARE. On the other hand, my understanding is that in the Gulf states neither Dr Huey nor R. multiflora is suitable for the kinds of challenges posed by the soil - its diseases, its parasites, and its tendency to burn organic material quickly. There is a question in my own mind, though, whether the idea that "grafted roses are always worse than own-root roses" applies equally to grafted roses on other rootstock such as fortuniana.
At the end of the day I think it's really hard to make any sort of blanket judgment about whether grafted or own-root roses are better - in general. I think one can consider a rose cultivar and a location and make a judgment about which kind of rootstock is likely to give a rose its best chance of growing vigorously or surviving a long time (sometimes the same thing, sometimes maybe the opposite). There certainly are a lot of OGRs that do perfectly well on their own roots. Many grow vigorously, some build up slowly but surely. Furthermore, there aren't that many cultivars that are offered on multiple rootstocks. Sometimes there's not a lot of choice.
I love the idea of growing roses that will persist long after I'm gone. I also need some success with roses in the present tense and in the near future. I pretty much avoid buying hybrid tea roses from VG and RVR. Since the weather here works for HTs, though, I grow them when offered on multiflora or Dr Huey rootstock. I do buy own root OGRs, shrubs, and floribundas from VG, from RVR, from Heirloom, and from ARE. And I delight in all the different kinds of effects offered by the plants that succeed.
