.... not following you exactly .... are you describing the union between the scion and the root stock? If so, it just sounds like the soil is collapsing (breaking down into smaller particles & settling). If you think that assessment is correct, you can just top off the containers w/fresh soil.

Al

Yes, Al, I think you hit the nail on the head. I just purchased these roses this year at our local Home Depot because I belong to our local Rose Society and wanted these two roses---Tropicana and Gene Boerner. I bet they need to be transplanted. I had these two roses before and love the blooms. I am not a sprayer so decided to use them as annual containers and if I lose them, then that is it, but I wanted to try and keep them over in my little unheated attached greenhouse. I separated my shoulder, so having a little difficulty doing any outside work now. I think there is no room in these to add enough soil to cover the bud union, but I can try. Thanks for the advice. Barb

Roses, I don't know about, but in any kind of fruit tree, that graft union is supposed to be above the soil.

Is that different in roses? I'd love it if someone could explain why because I'd like to learn about roses.

Barb, I am sorry we live so far apart. I wouldn't mind puttering around in someone else's garden for a few hours if they needed some help.

For roses, the union is most commonly at soil level or just above -although in the colder zones it is recommended to plant the union a few inches below surface so that some part of the cane above the rootstock can survive a severe frost.
However, even in milder zones, there may be some advantage to planting deeply so that roots will develop both above and below the graft. Roses grafted on briar rootstock establish very much faster than roses on their own roots but own root roses are said to have an indefinite lifespan as compared to grafted. Planting deeply can be a way of having the best of both worlds.

Trees, on the other hand - do not take well to having their bark underground. A nurseryman friend tells me that one of the most common reasons for newly planted trees failing is that they are planted too deeply.

barb roselover in, one of the reasons for grafting is that the rootstock is able to withstand/overcome a problem in which the scion by itself would be at a disadvantage.(e.g. nematodes in the soil/potting medium).
If this is the case, it would be better to have the union clear above the soil line.