Hi, Jim. My name is Kim Rupert. I've been exploring my rose obsession for nearly three decades, which doesn't make me an "expert", but I have observed and learned a few things. Lyn quoted Ralph Moore, whom I've been honored to have as a dear friend for over twenty years. He named a rose for me a year ago, which you may view here on HelpMeFind. You can also view some of my rose creations here if you look me up in "Rose Breeders". Ashdown, Uncommon Rose, Sequoia, Amity Heritage and others have and do offer my roses commercially. A number of my rose articles have appeared in newsletters and the American Rose Magazine here in this country, and in Europe. You can read quite a few of them here on HelpMeFind. For nearly sixteen years, I developed and maintained a large collection of roses (roughly 1,200 plants, MANY of which I rooted) on a desert hill side here in the mid-Southern California desert, until I downsized it several years ago due to construction.
I have given slide presentations to roses societies and at a Huntington Old Rose Symposium, and I consult with people about their rose gardens here in northern Los Angeles County as part of my job. I've grown roses here in the desert and I grow them within walking distance of the Pacific Ocean at the beach.
I began volunteering 23 years ago at The Huntington Library in San Marino, California, propagating roses. For several years, a friend and I generated several thousand own root roses of ALL classes for their sales. Between propagating there; growing hundreds of own root varieties; observing them all over California; and spending many, many hours with Mr. Moore and haunting Sequoia Nursery, I have observed you can't make accurate blanket statements about roses, or much of anything else. Once you've studied as many plants in as many places as possible over many years, you'll notice some things which do seem fairly consistent. First, not all roses will root. Some root like weeds and grow beautifully own root, while others don't seem to have sufficiently developed cambium layers to callous and generate roots well. Even those which do root well and grow well own root, can have more limited ranges of soil, temperatures, water type and frequency, etc., than the established root stocks may.
I can say, with some certainty, in areas which aren't extremely cold and where minimum cultural requirements are met, many modern and nearly all Old Garden Roses perform as well, and sometimes even better own root than they do budded. Remember, budding and grafting were not common methods of propagation until the Twentieth Century. Well into the last Century, the established method of rose production was own root cuttings. Modern Roses introduced prior to the 1920s were mostly offered own root, (as were all Old Garden Roses for a few centuries) so they had to root and grow well own root or they didn't get introduced. (Much like miniature roses today)
It wasn't until J&P and a few others chose to bud to produce larger, stronger plants in less time than rooting could, that budding began to become the standard. The vast majority of miniature roses have always been propagated own root. Many budded roses planted with the bud union below the soil surface will frequently root and continue as own root plants. Many roses will layer and root in place when canes are in constant contact with a suitably damp soil surface.
In the 1980s, I imported quite a few roses from growers in England. Harkness' 'International Herald Tribune' came budded. As I'd planted it on a rather steep slope, soil washed down with each rain and watering, until the bud union had been fully buried. I had to move the plants a few years later and instead of digging up the two plants I'd originally planted, I unearthed a dozen, own root plants! Rooting 'International Herald Tribune' in the mist propagator at The Huntington for a rose sale, we struck twelve cuttings and removed thirteen plants from the pot two weeks later. The bottom bud of one cutting actually grew a root and fell off the stem when I removed it from the medium. I carefully potted this one growth bud with a small root projecting from it, and watched it as it grew into a completely sellable plant within a few months.
Harkness' Hybrid Hulthemia, 'Euphrates' also experienced the erosion on that hill, and it rooted in many places! I had enough own root plants to give to just about anyone who wanted one! It was like digging up a black berry plant, layered cutting grown plants all over the area the plant covered. As for "hardiness", those in harsh, cold climates have for years sought own root roses because those which tolerate their conditions are HARDIER own root than budded. 'Dr. Huey', which is the major root stock used in this country is rated as hardy to Zone 6 and higher. What do you do when you live in Zone 5 or lower and you want to grow cold hardy roses? There are roses which will endure extremes far lower than Zone 6, but if the only roots they have are often only hardy to Zone 6, you run a great risk of the roots being killed, resulting in the loss of the entire plant. If you grow your 'Maidens Blush' (rated hardy to Zone 4) own root, it will likely endure much colder and harsh weather than 'Dr. Huey' and come back for more. 'Dr. Huey' will probably freeze to death at those extremes.
Many more recent modern roses, those introduced after the 1920s, will root beautifully and develop into wonderful, productive plants. At The Huntington, there stood for many years a bed of 'Iceberg' bushes. They were in a very unfortunate location, being heavily shaded by over hanging trees and having to compete with extensive tree roots. Clair Martin, the Curator of Roses used to chuckle every time he showed anyone around the gardens. Most of the bushes were fairly uniform, except for a few which were significantly heavier and huskier. All endured the same awful conditions, but the budded 'Iceberg' were consistently smaller and thinner than the own root plants. Right beside this bed stands the huge iron pergola in the Main Rose Garden. On each of its four corners there is an enormous 'Mermaid' rose planted. All four were initially budded, but one died. We rooted a replacement and within two years, you couldn't tell which was own root and which were budded unless you knew which had been replaced.
When labor was cheap, budding was a great way to produce rose plants. But, as wages, insurance, work place restrictions, etc., increase, budding is getting far too expensive to be the primary method of producing rose plants. Much of the rooting process can be computerized, making it more consistent and producing a superior "crop" of plants at a greatly reduced labor cost. As more and more introducers switch to own root, you're going to see more and more new varieties which won't be introduced unless they DO root easily, quickly and well, then perform well on their own roots. A good case in point is J&P's 'Henry Fonda', a brilliant yellow rose which is great here in Southern California. They'd initially produced it as a "New Generation Rose", an own root plant, but it failed to perform well over their required areas and has been put back on the budding list.
Conversely, the Old Garden Rose, 'Mme. Alfred Carriere', a Noisette, produces huge, thick wood easily and quickly own root, making budding it a waste of time. Many Teas and Tea Noisettes take time to root and a while longer than budded to develop into large plants. But, they usually DO result in husky, productive, extremely long lived plants on their own roots, OFTEN out living budded plants. And, with NO root stock suckers as there is no root stock.
One reason, for some rose types, I would suggested budded plants is for any rose which suckers own root. Species roses are known for colonizing areas by suckering. Rugosas and some other Old Garden Rose types, also sucker madly. If you want to grow any of these without having them take over your entire garden, a budded plant will prevent them from helping themselves to more acreage than you wish to allow them. If you want a colony of a particular rose which suckers, you either want it own root, or you want to bury the bud union deeply enough so it roots and begins throwing itself throughout your garden. Jim, have you ever been on a "Rose Rustle"? It's where "Rustlers" go out into abandoned towns, cemeteries, and homesteads seeking roses which have remained long after the humans who planted them have died or moved on. Many previously thought extinct roses of many classes have been rediscovered in these mostly inhospitable places, surviving for decade after decade without any human assistance, and nearly universally on their own roots. Many more are grown and offered commercially under study names until their true identities are discovered. Go here on HelpMeFind and take a look at those which have been listed.
Then, take a look at the offerings from Vintage Gardens, a sponsoring nursery here on HelpMeFind, and look at the "found roses" they offer. As for own root roses being bad plants, remember, all of the roses propagated by Vintage, Ashdown and Sequoia (not to mention dozens of other small nurseries here and abroad) ARE own root. Obviously, these producers and the many thousands of their satisfied customers, know many roses DO have sufficiently hardy, vigorous and strong root systems and DO develop into good garden plants.
I "discovered" a "found rose" in Crestline, California some twenty years ago. It had grown for years beside the drive way of The Mulberry Tree Antique Shop in town. I asked about the rose and the owner said she'd been trying to get rid of the plant, but it refused to die! It was scraped off at the ground level by snow plows every year. She dug it out and it frequently endured doses of salt thrown on the ground to melt the snow and prevent ice from forming. I asked if I might collect a piece to grow and she told me to dig it up as it would NOT die! She was right! It grows in a bed at The Huntington Library and was even offered under my study name of 'Crestline Mulberry' by Arena Roses in one of their first catalogs. This rose went through Hades every year, even tolerating shade, salt and hard freezes, ON ITS OWN ROOTS, and it refused to die. I don't know about you, but I would call that "HARDY".
Yes, there are some roses which will not perform well on their own roots. Two immediately come to mind. I love the off beat roses, those with odd colors. 'Grey Pearl', "The Mouse", is a 1945 McGredy Hybrid Tea. It is a "love it or hate it" rose because of its very unusual color. It has what has been called a "death gene". It will develop a strong, vigorous cane topped with a large cluster of its magnificent blooms, then die to the root. It makes sense to me. The color would never attract a pollinator insect, so why would Nature waste good genes on it? It would NEVER succeed in Nature without Man's intervention. This rose will root, but it will NOT develop into a good, productive plant. And, own root, it will die to spite you! A similar rose, introduced in 1959 by Meilland, 'Fantan', is even worse as a plant. Even budded, it is a weak, sickly thing which teases you with an occasional exquisite flower. Own root, it is a train wreck!
Back to The Huntington...for years, they've grown a huge bush of the 1927 Hybrid Tea, 'Autumn'. Each year, this plant grew six to eight feet by about the same. It was usually covered with long stemmed, fragrant, multicolored wonderful flowers any time it was warm and sunny. This ancient plant is own root. It is heavily virused and grows in the shade of some of the same trees which shaded the bed of 'Iceberg', yet, it still grew and bloomed like a huge weed! I've often joked that budding 'Autumn' would act like a dwarfing agent, like the dwarfing root stock you use to create dwarf and semi dwarf fruit trees. 'Mr. Lincoln', 1965 Hybrid Tea, at least here in Southern California, is another which gets huge own root. And, blooms its head off!
Jim, once you've had the opportunity to observe many roses in many different locations, under many different conditions and cultural practices, you'll begin to see what Mr. Moore has always said..."Once you think you know the rules, the rose goes and changes them!" If the rose is vigorous and if it roots easily, it will likely be a good own root specimen as long as it's properly taken care of and not in a climate which is unsuitable for it. If it's a weak, sickly grower budded, it's likely not going to make a good own root candidate. If the rose was introduced prior to the 1920s, it will more than likely root fairly easily, and will likely grow well in its temperature zone range, provided it's given the minimum care, or benign neglect, it requires.
There are just too many variables in roses, as well as in life, for anyone to make an absolute, blanket statement and expect to be correct. The best you can expect to do is to qualify your statement with something like, "in my observation", "in my climate", "under my conditions and cultural practices". At least then, you can make hard statements like you've made and not hang a target on your chest.