Heirloom means they have grown their unindexed stock plants for years with no sign of virus. They have never knowingly propagated virused roses. RU, on the other hand, has done so, and I got a couple of virused plants from them just a couple of years ago. But they are doing much better than previously. Probably some of their more obscure varieties (including minor Bucks and un-famous older hybrid teas) are not available anywhere virus-free.

Buy indexed from RU first--they are bigger plants than Heirloom's and more likely to be correctly labelled. If neither company has a variety indexed, Heirloom's is more likely to be virus-free, but the tiny band plants are a negative factor in zones 4 and 5. So it's not an easy call.

I'm on the line of growing zone 5b and 6a and Heirloom roses are like army tanks here.

BUT, with your colder zone 4, I agree with Michaelg's statement.
"If neither company has a variety indexed, Heirloom's is more likely to be virus-free, but the tiny band plants are a negative factor in zones 4 and 5. So it's not an easy call."

You would have to winter-protect those from Heirloom and RU for the first couple of winter seasons until they get more established.
And depending on how cold & cane hardy they are, maybe beyond that.
I have no idea what type of roses you plan on buying?

I've gotten a few Heirloom roses this year and last and they grow like gangbusters for me! Never had any problems with them at all so far.
Next spring is my first RU order, so I can't say about them yet... :) But I do hope that the rose I ordered is not virused, as I shovel pruned a virused rose to replace with a "clean one" from RU.

I've ordered from both Roses Unlimited and Heirloom and when I had both plants by spring then by fall you couldn't tell the difference. The Heirloom plants start smaller but they're healthy and grow fast. I've never noticed virus in any of my roses but I haven't really looked for it either. My Peace might not get blackspot as easily if I had a virus-free version, but I might lose the lovely scent if I bought a different one so I'm willing to put up with the possible virused version.

I routinely order from both Roses Unlimited and Heirloom, and have been very pleased with plants I've received from both vendors. However, my experience has been quite different from Athenainwi's. Whether OGRs or modern roses, it's always possible (at least for the first several years) to differentiate between the roses that arrived as bands and the ones that were supplied by Roses Unlimited or the few other sources for larger ownroot plants. I've learned to purchase bands ONLY if the variety is otherwise unavailable.

Thank you for the good points and useful guidance. I'm rethinking how much to purchase from Heirloom, as the price is not much different b/t the two, but the size apparently is very different.

If I took a chance and ordered something from Roses Unlimited that is not virus indexed, how likely is it that I would end up with something virused? Is it 10% likely? 50% likely? 90% likely? I'd like to know the odds before deciding. Any guidance based on your own experiences/knowledge would be much appreciated.

Also, how many years does it take a virus to show itself in a rose?

Thanks!
gardenzerzone4

Virus may never show itself, or it may show in the first spring spent outdoors in the cool.

The probability of virus from RU depends on the type of rose. Less likely to be virused are newer roses and roses that were not mass-produced in the USA during the 40s-80s. Buck roses and older hybrid teas/floribundas are more likely to be virused unless indexed.

I was at a rose talk recently & the speaker said that there where 4 identified rose viruses for many years but recently new virues were being identified because of better availabilty/lower costs of things like electron microscopes to plant pathologists so now there are close to a dozen identified rose viruses known. When the question of "rose indexing" came up, he stated that "just because a rose is indexed' does not mean it is virus free" & he explained it this way. When you do the indexing test, you can only do it for one of the viruses at a time so it will only tell you if that specific virus is present or absent, but it tells you nothing about the presence or absence of any of the other viruses. Does that sound right or can someone explain it better or provide a link to a good article on rose indexing?

Yes, virus indexed roses can contain viruses that they were not indexed for. See the linked to an earlier thread for an example involving U. California Davis indexed roses.

Of particular concern is that at least one of these "so called new" viruses is spread by aphids. (They actually are not "new' they were simply not tested for.)

Here is a link that might be useful: linked to earlier thread

Thanks Henry. Yes my speaker mentioned that one of these newly ID'ed viruses was insect vectored & also said that there was significant anecdotal evidence that some viruses were spread by natural root grafting when a infected rose bush was grown next to non-infected rose.

If you are interested and willing to search (Google or Bing), check out some of the articles on AGDIA, which is a company that makes tests for viruses and other diseases of plants. You can see the PCR and ELISA tests that are available for roses (and for many other plants.)

Do you know the word "Synergy"? Not the new age version, but the science based synergy- there are some interesting plant pathology sites out there as well. Briefly, Synergy means that diseaseA has X symptoms and disease B has Y symptoms, but when a plant has diseases A&B, the plant will not have a simple mix of X and Y symptoms, but often will also have new (call them Z) symptoms that may be worse that the sum of X and Y.
Where does that leave rose growers? It leaves rose growers wanting to keep their plants as healthy as possible so that no even more damaging symptoms appear.

Years ago a simple study was done in California roses. Under optimum conditions, roses with a single virus (as tested for back then) produced ten to fifteen per cent fewer blooms. That, economically, was reason to keep the plants as clean as possible.

And to the root to root transmission: Google Scholar papers by Giolino (author), roses, and the time period last ten years.

The 1997 Rose Hybridizers Association thread (linked to below) touches on points similar to those brought up in the present thread.

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Also, a recently posted (2010) University of California, Davis Cooperative Extension article recommends the following precautions against above ground spread:

"In the meantime, you need to remember that viruses can be transmitted by pruning and cutting shears. Virus-infected plants should be pruned last and/or have their flowers harvested last. To be extra cautious, wipe your cutting shears with alcohol (rubbing alcohol is good) or a 10 percent bleach solution between plants."

http://ceventura.ucdavis.edu/Coastal_Gardener/Rose_Virus.htm

Here is a link that might be useful: 1997 Rose Hybridizers Association thread

There is probably no such thing as virus-free. Viruses have been reproducing within DNA for a very long time. There are all kinds of viruses. Some viruses are invisible to the eye. We're just beginning to see them identified in roses through genetic testing. Our knowledge is in its infancy.

If you're talking about Rose Mosaic Virus, seedlings should be virus-free... for a bit.

Personally, I've been unimpressed by some of the VID (virus indexed) roses I received. In fact, I have one rose that is more vigorous virused than VID. Now this doesn't mean that I keep many roses with RMV. I try to remove virused roses from my gardens unless the plant has grown into an outstanding specimen and the symptoms of RMV are invisible. I remove anything with visible RMV or with other oddities or deformities of foliage, but I don't delude myself that my garden is virus-free. And I don't let others deceive me by claiming their roses are virus-free because no one noticed any symptoms.

Some cultivars released in the 50's and 60's, and this includes some Buck roses, are virused because the releasing producer was notorious for using virused rootstock.

My Maria Stern showed the Rose Mosaic Virus in the first spring after planting. It wasn't too bad the first year, but this year it looked worse, so I did shovel prune. I figure I might as well, because even if others don't notice it much, I do! Every time I would walk by it this year, I would see all the mosaic patterns on all the leaves. That, and it gets me a little concerned when people start talking about the possibility of the virus being spread by vectors like aphids. So, out it went!
Maria Stern also was the last one I would prune or "mess with" for the day lol.
I have also read that just wiping your pruners with the bleach solution, while ok for between cuts, isn't ok to really kill the viruses. I read that you should soak them for 10 minutes after you are done working with them for the day.

The statement was made: "If you're talking about Rose Mosaic Virus, seedlings should be virus-free... for a bit."

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H. Kuska comment: The most common virus in the RMV group is considered to be PNRSV which has been found in 2 batches of rose seedlings in England and reported by several U.S. hybridizers in northern climates to occasionally occur.

Recent U.S. Davis, California research that has reported no seed transfer was done in a climate that has hot summer day temperatures. PNRSV is a temperature sensitive virus, and roses have an immune system against PNRSV that is most effective at higher temperatures. See the following link for more detail.

Here is a link that might be useful: link for pollen transfer discussion

Brownell roses like Maria Stern are highly likely to be virused because they were propagated by cheap producers during the period of maximum carelessness and they are not popular enough to have been virus indexed.

Brownell roses like Maria Stern are highly likely to be virused because they were propagated by cheap producers during the period of maximum carelessness and they are not popular enough to have been virus indexed.