This year, for the first time, I have had to seal all of my pruning cuts.
sunnyvalley said:Goodness me!! All of your pruning cuts 
How many roses do you have? It would be most time consuming even only on a few bushes! I have never noticed the stem borers going in via the pruning cuts here. I think the cut are well healed by the time they become active. I see more damage on new tender young canes.
I have about 100 established roses on five levels. There is a wasp up here that drills holes in the canes to lay eggs, but the damage only goes down about two inches. With the raspberry cane borerers, it's a different story. They will drill all the way down to the bud union and can kill the rose.
sunnyvalley said:Lyn I tip my hat to you. one is never too old to learn!
Sharlene, I felt I had to write that "caution.". This thread has had over five hundred views. Not everyone reading it has the experience to know that what is true for me in my garden may not be true for them in their garden. I am hoping they will jump in and join the conversation. It's fun to have people of all levels of experience posting to a forum.
sunnyvalley said:I have read and received a lot of contradicting advice about growing roses and as you say, what works for one might not work for the other. Your cautioning has been noted and is appreciated!
And, BTW, I am keeping an eye on those canes which I did not remove and I am sure Neal will as well.
sunnyvalley said:Speaking of contradicting advice - I was speaking to a local rose grower the other day about growing roses from cuttings. I have never bought an own root rose and only have what I have grown from cuttings and the roses I have bred, so I don't have much experience growing own root. He, however, stated that own root modern roses are not as winter hardy as grafted Confused Blinking I thought I wasn't hearing right???? Not the answer I expected from an 'expert' when considering what I have read or noticed in my own limited experience. Certainly, I have read that there are roses which just don't do well unless grafted and which would probably not be very winter hardy on their own roots but to generalise about all modern roses ....... It seems to me the trend towards own root is growing in the US - am I mistaken???
I love this kind of question
because it involves rose history, rose botany, rose lineage and the rose industry. I'll have to skim over some of it or else I'll be writing a book ...
Thankfully, it is raining and I don't feel guilty about not being outside working ..
I can understand why your "expert" got the idea that grafted modern roses are hardier than own root, but that is not quite accurate. However, he is probably correct that they do need to be grafted to survive in the colder parts of Europe. I'll get back to this below.
Hardiness, or cold tolerance, is determined by the lineage of the rose. European species roses adapted to growing in a cold environment by going dormant during the cold months. They pulled all of their nutrients from the canes and sent them to the roots so that when the soil warmed up, air temps warmed up and there was more light, they had the resources to regenerate and grow back. The old garden roses of Europe were bred from these species.
When the repeat blooming gene was introduced into the gene pool in Europe, it came from roses that were bred from species roses that never had to go dormant. These roses store their nutrients in their canes when they slow down during the winter months due to cooler temperatures and lower levels of light. They also do not remove enough moisture from inside their canes, so that when the canes are frozen the cells burst and the canes die. If these roses lose their canes, they do not have the resources to regenerate and grow back.
A broad definition of "modern roses" is that they are the classes of roses with repeat bloom. Therefore, in general they are not cold hardy.
Back in the early 1800s, roses were grafted simply to increase nursery inventory. (That was true even in the US until the two major distributors, Jackson & Perkins and Weeks Roses went bankrupt.)
When nurserymen, budded the tender repeat blooming roses to the cold hardy root stock they had available to increase their inventory, they discovered that these "tender" roses were more cold hardy. Actually, it was the root stock that was cold hardy. As long as the bud union was protected and did not die, a tender rose could die back almost to the bud union and come back the next year because the root stock held nutrients that had been stored from the previous growing season.
They also discovered that roses that were lousy plants on their own roots could become vigorous and healthy plants, if they were grown on a more vigorous root stock.
So, even tho' the nurserymen only intended to increase their inventory by grafting, they discovered a few additional benefits to budding a rose.
There were a lot of roses that could have done very well as own root plants, but they were never tested as own root plants. When a seedling was selected to be tested, they budded the plants and tested the roses as budded plants.
Now, back to your expert. The modern roses are probably too tender to survive in the colder parts of Europe on their own roots. They simply are not genetically programmed to go dormant and survive the colder temperatures. By grafting them to a root stock that is cold hardy and protecting the bud union, these roses can be grown in colder zones because the root stock has the proper genes needed to survive in the colder conditions.
Neal, there is a LOT of misinformation about own root vs grafted in the US.
Back when you were a teenager, 'Dr. Huey' was the rootstock of choice because it was the most adaptable to various soil ph levels. What the industry never told anyone is that Dr. H is only hardy to about zone 6. Also, the concept that roses are regional was one that the industry never admitted to until the death of the AARS. That's another book ...
for the encouraging words.
