Roots are more tender than tops. If the center of the root ball freezes to a certain temperature, the rose will be killed. For the shrub rose that is cane hardy in your climate, the canes need no special treatment--being in a pot doesn't affect the exposed parts.

I've had good luck with moving the pots to a sheltered location and maintaining a pile of leaves around the pots and covering the soil. Canes of hybrid teas can use more protection during the time that temperatures fall to ~10 degrees F. This could be an additional 12" of leaves or straw. But covering the canes during periods of mild weather can lead to damage from canker disease. If under the eaves, the pots need water once a month.

Hi Fife, I've just put all the info on how I winter my pots on the thread below. Check it out.

Here is a link that might be useful: Wintering pots

The problem can be defined as what can you do to help the rose when it goes below zero, that doesn't hurt it when it is forty degrees and raining. Coverings over the canes fail the forty and raining test. Garages are so far one of the few things that don't. Leaves, straw, containers without extremely excellent ventilation - all those can cause serious damage.

Be aware that garages often protect small rodents from predators--many CT gardeners have protected their roses from winter weather--only to find that all the bark has been stripped from the canes.

No matter where or how you winter them there are risks. And critters can damage even the ones planted in the ground. I had several that were eaten to the soil line one winter when rabbits decided to nest in my rose bed. Best protection against this is wait as long as possible before starting any winter protection. A lot of the problem is that people winterize too soon. There's a little nip in the air and a bit of frost and people start putting everything down for the winter. You have to wait until everything is completely dormant and the ground is frozen. Then chances are most rodents will have already found their winter quarters and won't move into your nicely mulched roses. I wait until December now to do any winterizing but even then it's all dependent on the weather. Inside an unheated garage is still the easiest and most effective way of wintering over potted roses. If I had a garage that's where I'd put mine but since I don't they have to stay outside in the winter pot ghetto.

{{gwi:324563}}

Since there are over 40 of them it would be too labor intensive to sink them so they stay above ground, wrapped in burlap and packed with leaves. This has worked for 6 winters now and I've never had rodent damage in there. Nor have I had problems with canker or diseases.

Seil, remember you are much drier during the winter than we are. Also, even here the ground rarely freezes and stays frozen the entire winter. In a warmer place, there is even more freeze-thaw.

Thank you all for your suggestions.

I don't have a garage, but I do have a shed. I don't like the idea of putting them in the shed because I know there are rabbits and chipmunks around.

Winters here can be very mild, and we rarely have a dry cold winter with consistent snow cover. We do get a lot of mild, rainy days, so I'm a bit leery of packing them with leaves or straw.

I might just bury the pots, mound soil over the base of the plants and surround them with filter fabric to protect them from the winds.

I have a few minis that I grow in pots in my z4 garden & I used to dig a trench, take them out of the pot, lay them on their sides and bury them. This worked well but it was a lot of work digging them out in the Spring. Now I dig a hole in my veggie garden & set the potted rose in upright so the pot is only 1-2 inches below grade, back fill around the pot & mound 8-10" of soil on the rose. Had good luck with this method & a lot easier to dig up in the Spring. If you have clay, ceramic or similar pots you would need to remove the pot as they probably won't take the freezing.

When I first moved to the mountains of northern California, I was "gifted" with over 100 roses in small bands. I really didn't have time to deal with roses that year because I needed to do the deferred maintenance on the house I purchased. Since I had never experienced a real winter ... and I know my winter is nothing compared to those of you who live in colder zones ... I had to figure out what I was going to do with these new plants.

I didn't know that they were supposed to be potted up gradually and decided I would put them in the largest pots I could get and count on the soil in the pot to act as an insulator for winter. Then because, I knew I had to over winter them outside and that we get on average 40" of rain during the winter months, I was afraid I would still lose them.

In theory, it takes longer for a larger mass to freeze than a smaller mass. I clustered the pots together in a part of the yard where they were protected the cold air from the slope. Then I surrounded the pots with large bags of leaves and stuffed smaller bags of leaves between the pots to create as large a mass as possible.

Even when it snowed, I didn't go out and shake off the soil. They were on their own until it was time to take the hoses out for spring.

As I developed the garden, the cluster got smaller, but I used the same method for several years. I only lost one rose.

Smiles,
Lyn

What a "gift" Lyn. I am in a bit of the same boat this year as we will be doing some construction that will not allow me to put my potted roses into the ground. I'm in 7a. Last year we barely had any freezing temps at all. I had a few OGR's in pots that I just left out for the winter. I'm not sure there was even dormancy???
My yard is Southern facing and fenced. I don't believe the ground has ever frozen. Maybe a crispy frost layer but that's it.
I intend to put mine up against the Southern brick wall. I've read that here in Nashville I should not begin winter protection until we've had 3 successive nights of freezing temps.
My question is, if I am growing a rose that is hardy to Zone 6 and I am in 7A does it need protection?
Thanks
Susan

Susan: "Hardy" has three different meanings: crown hardy, cane hardy, and tip hardy. Except for a few extreme sissies, most roses are cane hardy to at least 10 degrees if they have been hardened off by extensive exposure to 40s and 30s. With 5-degree seasonal lows lately, I have had little or no damage to mature canes.

Roses in pots are more vulnerable to having the crown and roots killed than are roses in the ground. Roses in small pots need the pots and root ball protected before the canes.

"Three consecutive nights" sounds like a silly rule to me. The time to protect is when rose-damaging severe cold immediately threatens.

Basically rodents are lazy and opportunistic. They're much more likely to go after the ones at ground level and easy to find and reach than the ones they have to climb up pots to get to. They probably won't even know they're in there because they can't see them or smell them. I don't think there would be any problem putting your potted roses in the shed. Like I said earlier, I've never had rodent damage in the pots, only in the ground roses.

Lyn, your method is very much like mine and I based mine on the same principles. Since I don't have a slope I use the wall of the house as the major wind break.

michaelg...Many years ago I learn a winter rose protection rule that said "do not cover your roses until they have been exposed to 28F or colder at least 3 times" & this has always worked well for me in z4. The reason why for this rule was, too many people covered their roses & other perennials too early in the year, they need these cold temps to harden off. The only problem I had with this rule was, "is there a limit to the 'or colder' part?". A rose growing friend of mine answered that question from a study he heard about done at Boerner Botanical Garden which came up with 20F, "roses that need winter need to be covered when the temp drops below 20F" & that is what I use now.

wirosarian--20 degrees would probably be too soon for Eastern areas where we need to worry a lot about canker disease in winter, but I'm sure you know what works in your climate. This year I have a few small roses that I may protect when 10 degrees is impending.

michaelg...good point about "knowing your climate/region. I lived on the eastern side of my state 10 yrs ago where the soil was heavy clay, very poor drainage, pH near 8 & weather influence by Lake Michigan, then I moved to the western part where I was 1/2 zone colder, had sandy soil with excessive drainage, a pH about 5.5 & a climate influence by the prairie winds coming out of MN. It took me 4-5 years to get my rose garden looking decent.

I have been wanting to ask this question ever since I moved to the mountains. When we are talking about temps, are we talking about average temps in a 24 hour period ?

In my climate during the winter months, the night temps hover around 20F down to 10F, but the day temps are usually high 30s to low 40s.

I have never seen die back in this garden, but my "guess" is that the low temps are not low long enough to cause damage to the rose. I have never found any information in a rose book or online about how long the plants have to be subjected to cold temps before there is damage.

Does anyone know the answer to that one ?

Smiles,
Lyn

Older books used to have a lot of different ways of saying basically the same thing - damage starts somewhere a bit below zero for most hybrid teas. This could be phrased a number of different ways. Usually as temperatures below a certain point for a certain number of hours. Having spent many years in the same climate as many of these authors, I feel capable of translating.

Fife, I don't grow roses in pots, I grow them in the ground so my comments might not apply.

Placing pots in the ground and applying an even layer of mulch to the bed sound like a good idea, but I would not mound and I would not cover.

In my experience Hybrid Teas can tolerate cold, but don't like damp conditions. The mounding can create a very damp environment in our area.

mad_gallica...........

Thank you for your response. I've found that cold tolerance is not really my primary issue in this garden. It's heat tolerance that is more of a concern. I was just curious because I can find that kind of information about food crops, but have never been able to find it for roses.

Smiles,
Lyn

Lyn--not average temperature but low temperature is the issue. Of course a temperature would have to be sustained for an hour or two in order to penetrate the wood's self-insulation. If your seasonal low is 10 degrees, I would not expect damage to plants in the ground, but I would give some protection to small pots.

I have had plants killed by temperatures slightly above zero--Honor, Evening Star, and Mme Butterfly come to mind. These had grafts placed at grade level. I used to have substantial cane damage to most modern bush roses back when we had 6b winters routinely.

Thank you, Michael.

I got all of the roses that were given to me as a housewarming gift into the ground or given away, so I don't have to worry about anything freezing.

I don't do anything in containers up here because it's impossible for me to keep them properly moist during the months of high temps.

The reason I asked is that people up here ask me the same question, but usually they live at a higher elevation than mine and get colder winter temps. I have always had to say that I don't know because I've never tried to grow roses where the temps dropped lower than 10 degrees at night.

Smiles,
Lyn

Thanks again, all.

It looks like I sparked quite the conversation. Carry on...