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prairie_northrose

Winterizing / Winterising / Protecting Roses in the Far North

I have a few younger weaker roses (quadra & rugelda) planted in the ground that look like they may require winter protection. I'm not too concerned about my other more "hardy" roses, although I would like to do what I can to extend their growing season.

November was warm(felt like +10 or more yesterday), and all my roses were full of green leaves before today's sudden 10-15 cm snow and -20C temperatures. Being in the Calgary region, I don't expect much less.

It is amazing to see how the techniques on winterizing roses differ from region. I would love to hear your thoughts on this in colder regions, or in chinook regions.

There appear to be a two options for roses in the ground:
1. cover with snow
2. cover with peat moss / dry mulch / leaves (often combined with an open pot / styrofoam box / cardboard box / leaf bag / burlap / tarp) after the rose has gone dormant and the ground is frozen

What is the the purpose of protection then?

Is to keep the rose frozen? Or to keep the rose less frozen?

Last year, snow that was piled high here, eventually melted down into a hard ice-block mass, and ground underneath remained frozen for much longer than areas without snow. I assume in the snow technique, airy light snow is ideal.

The reading I've done suggests mulches that become wet increase the risk of canker, if so - does snow too? In the mulching techniques, dry mulch and adequate airflow is emphasized.

I do believe that in both cases, a common goal is to protect canes from the cold harsh & dry winds. There is also emphasis on planting the rose 6" deep and watering well in the fall.

Curious, what works best for you?

Thank you for any thoughts!

Comments (18)

  • shillanorth Z4 AB
    9 years ago

    I am not one to fuss over any plants in the garden. All I do is make sure there is a layer of shredded cedar mulch on the garden in an effort to discourage too much freeze/thaw action - no reliable snow cover here in the chinook zone. Everything gets a good haircut in the spring as all the canes die back to ground level. I have Winnipeg Parks, Morden Sunrise, Campfire, John Cabot and Mai Gold and although they were well behind what they were the year before, they all made a decent showing this year.

  • don555
    9 years ago

    Not sure if my experience will be helpful since I'm growing some hybrid tea and floribunda roses so I expect them to die to the ground each winter since they are rated zone 5 and up. I've had the roses for over a decade now and each summer they get about a metre high, flowering pretty much until frost wipes them out.

    I'm in Edmonton so get a steadier snow cover than you in Calgary. I planted the roses with the grafts at least 15 cm below ground level, and the plants laying at about a 45 degree angle to maximize the amount of stem underground. Looks weird for the first year only. My goal is basically to make sure everything underground stays alive so the plant has good energy to put up new shoots each spring. They almost seem to explode out of the ground in late May or early June.

    In late fall I cut the plants down to about 30 cm and clip off and remove any remaining leaves (remove disease source). Then I cover the entire bed with about 30 cm of dry leaves or loose straw. If I use leaves I need garden fencing to prevent it blowing around. Straw sticks to itself pretty well here, but in the chinook zone you might want garden fencing and/or a cover of burlap to hold it in place. Once the snow is gone from the yard in the Spring I begin removing the mulch, usually have to do this in stages since there will be ice near the bottom. Very occasionally some of the very lower stem survives, but the new growth from the underground stems is always much more vigorous.

    Your roses are semi-hardy I think so you probably want to save the above ground parts too. I have used mulch to protect some Morden roses here as well and it does seem to help. But I've stopped doing it lately because it's such a bother to remove all the bits of straw from the branches of those unpruned branches in the Spring.

    As for general mulching thoughts... I think in your case the goal would be to prevent the plant breaking dormancy due to a Spring chinook, then freezing when colder weather returns. So it's to moderate the weather changes. You apply the mulch after the ground has frozen so that you don't end up with the plants held in a moist unfrozen environment where molds and such can grow. In my case, I put on all my mulches yesterday when I saw that the snow we were getting was not melting so the ground was at or near freezing.

  • SouthCountryGuy Zone 4b-5 SE BC
    9 years ago

    I am in a much different climate than you but having the same issues. I have quite a few roses that are still quite small and I am worried about them surviving.

    I prefer not to fuss over plants either being the lazy gardener I am but I think I am going to pile mulch up around the 'weak' roses and freeze them in.

    I do know a gardener in Calgary that has lots of roses that gathers enough bags of leaves to cover the whole rose bed which she then covers with a white tarp. With this method she manages to keep quite a few tender roses alive.

    One of our forum members commented that Calgary was the "New York of New York" in the gardening world. If it can make it there it can make it anywhere!

    Good luck and keep us informed on what you do and how it works out in the spring.

    SCG

  • weeper_11
    9 years ago

    I have trouble with mice and voles makes homes in any thick mulch I put down for the winter; they seem to be attracted like magnets to the roses that I put straw around. So it is always a toss-up for me: do I want to risk them dying back too hard, or do I want to risk having voles girdle them?

    I was very surprised that my Alba roses made it through just fine last winter, and didn't even have any dieback, because I forgot to cover them! They must have had good snow cover. So I'm not sure what I'll do this year. I'll probably use some straw, just in case.

  • northspruce
    9 years ago

    I'm in a third category: reliable snow cover, but I grow mostly old roses that bloom on old wood, so I need them not to die back. I use leaves and burlap, and bend the stems down as much as possible.

    I let the ground start to freeze, and the leaves turn yellow &/or fall off (some varieties go dormant more readily than others) before I cover things up. I just did mine on the weekend. This allows the sugars to be reabsorbed into the canes. So yes, the purpose is to let the plant freeze but at a stable temperature that's not too cold and not freeze-thaw cycles.

    I also used to use straw and I had rodent problems. I assume it was the seeds left in the straw that attracted them, because I haven't had any problems since I switched to plain leaves.

    I don't know what I'd do in Calgary. I really rely on my snow cover and I continually shovel it deeper over the roses all winter.

  • shazam_z3
    9 years ago

    Rugeldas require no protection.

    I have a Quadra that I don't do anything to, it's doing fine. Very little winterkill.

    Option #2 you listed keeps temperatures higher and more stable, keeps light away thus preventing dormancy break (roses require light to break dormancy) and prevents wind from sucking away moisture.

  • weeper_11
    9 years ago

    I'll have to try using leaves, then, northspruce! Hopefully that will help my rodent problem.

  • xaroline
    9 years ago

    You can also buy "rose huts" to protect roses.
    I use them on John Davis,--- not for the cold , but because the bunnies like to chew the rose down.

  • prairie_northrose (3b north of Calgary AB, Canada)
    Original Author
    9 years ago

    Interesting thoughts, thank you everyone!

    I am leaning towards Option 2 for the weaker roses. It gets incredibly dry and windy here, snow does not seem to melt as much as it simply dries up. We are about 60k north of Calgary. There is a subtle colder weather difference, and we are also on a open lot that gets lots of north wind. In the future, I hope to build a more sheltered microclimate.

    The leaves of all my roses never fell off before the snow and -20C freezing temps. I hope this does not adversely affect them. And now they are calling for +3C on Monday!

    Too add to my confusion, I came across this interesting article, "In order to help us solve our question, we might ask: âÂÂAre there any scientific studies to help us determine whether winter protection is necessary or not?â There are but they only help to muddle the issue. In Chicago, results of overwintering records��"8,500 of them during the fifties��" seemed to prove Dr. WestcottâÂÂs later contention that winterizing was not essential. The best type of winter protection resulted in over twice the percentage of plants lost than when no protection at all was used. No one could deny that that seemed to bear out Miss WestcottâÂÂs conclusion. But, during the same years, in Cincinnati records were kept on 2,700 plants and the results clouded the issue, in fact, one could say the results were stunning, because they came to the opposite conclusion. Eight times as many unprotected plants were lost percentagewise as were protected plants. What could one say, except that âÂÂwinter protection is necessary, maybe.â "

    Here is a link that might be useful: Winter Protection

  • SouthCountryGuy Zone 4b-5 SE BC
    9 years ago

    Prairie_northrose, Yeah, it is confusing. I have read so much on the subject it caused my eyes to bleed. I would like to know what the numbers were as they can be made to sound how you want. By that I mean maybe the Cincinnati test they lost 8 unprotected and 1 protected plant. Giving you what sounds like an astonishing difference.

    What I have determined is that it is much easier to do nothing and have winter kill than put a lot of effort in it and have it happen anyways. I have my grafts buried and am hoping for the best.

    I, too, am concerned as we had such a mild fall then went to -20 in 4 hours. The green leaves are still on all my roses.

    60k north of Calgary sounds like Carstairs area, I used to have family that lived there.

    SCG

  • alcan_nw
    9 years ago

    NorthRose,
    The article in the start of it aims to an audience in the state of NY I believe. They can have ocean influences that can make judging which method to use very difficult. The differences in cities of Chicago on a big lake and Cincinnati on the mainland are so opposite because living near an ocean or a lake can help any woody plant go into winter much easier than otherwise.

    You being in the praries will need protection because you are not near enough to the ocean or other large bodies of water so the choice should be more (hopefully) less confusing.

    This post was edited by alcan_nw on Sun, Nov 16, 14 at 19:10

  • prairie_northrose (3b north of Calgary AB, Canada)
    Original Author
    9 years ago

    Good points, thank you to everyone for providing pointing out the helpful information. I have to frequently remind myself gardening from one region to another can be vastly different. Or as DH jokes "just because it's one the internet must mean it's true." What amazes me is the subtle differences in microclimates within one region. We used to live on top of a ridge overlooking the bow river, there were subtle weather changes from neighbourhoods on top of the ridge, compared to close to the river.

    I have however been enjoying the info from book Growing Roses in Calgary from the Calgary Rose Society. It mostly suggests protecting tender roses similar to method 2 mentioned above. As this is year one of my rose garden, I am excited to see how things turn out next year. I would love to add some David Austin roses, I have read users on gardenweb in zone 3 who have had success. My mentality is if others can grow it, so can I! Seeing the photos of the grapes, blackberries and hydrangeas has been very inspiring. I had no idea these can grow successfully here until now.

    I'm lucky to not have many issues with mice or voles. We have two dogs that go crazy at the slightest scent of a mouse, and are frequently patrolling or peeing enough everywhere to deter critters.

  • SouthCountryGuy Zone 4b-5 SE BC
    9 years ago

    I have no experience with wilt-pruf but it is recommended here for plants to protect against wind. I would imagine you may have to apply a few times and am unsure of cost.

    If you have male dogs I would make sure to do some protection from them using your plants as a urinal. Maybe mine are special but they seem to target individual plants in the winter. I place rocks around or make a big cage to stop them. They have cost me several plants in the past.

    You are going to have to share pics in the spring. Sounds like it is going to look great!

    SCG

  • shazam_z3
    9 years ago

    MIL used Wilt-Pruf on new cedars last year and they survived perfectly (!). Not even a sign of tip-kill. I was impressed.

    The leaves staying on is theorized to be a defense mechanism - it lets animals eat the leaves and hopefully fills them up enough so that they don't go after the stem.

  • prairie_northrose (3b north of Calgary AB, Canada)
    Original Author
    9 years ago

    I never heard of the product Wilt-Pruf until now. Interesting. If I come across it or any other spray anti-transpirant, I am willing to give it a try. This would certainly explain the one of the reasons behind mulching is to prevent moisture loss to stems & leaves.

    It's a chinook right now (+5 and windy), and I can see rugelda's leaves at the base of the plant are still green, even though it dipped in to the -20s a few weeks ago. The branches up top certainly look drier/weaker and have dead leaves.

    Prairie Princess, is potted and no insulation right now. It has been in the uninsulated sunroom. It is the opposite - dead bottom leaves, and live leaves at the tips.

  • prairie_northrose (3b north of Calgary AB, Canada)
    Original Author
    9 years ago

    It has been +5-+10C all week, and now raining. Pretty much all snow cover is gone, the grass is green, and it feels like spring. I never know what to expect here for mid December!

    At the end of the day I would much rather have warm temperatures than cold.

  • wayne
    9 years ago

    It was a nice week here also, not as warm as there but so far we have had very little snow. I have not covered any thing but do have mulch around most of the roses. We had a long fall so the plants should have gone dormant.

  • prairie_northrose (3b north of Calgary AB, Canada)
    Original Author
    9 years ago

    I got some Wilt Pruf to try on the roses I'm trying to winterize in pots. Cost was about 22 bucks for a 0.47 litre concentrate bottle. The product pours out in a thick goop, and has an egg-yolk like feel to it. I thinned to the suggested 1:5 ratio for winterising and used a hand spray bottle. A small amount went a long way, I made about 500mL of product and likely only needed 250mL or less for two small bushes. Much was wasted using the spray technique. A brushing/wiping technique would be less wasteful however may be time consuming. Not sure if I will purchase any more of the product as I was slightly deterred by the subtle engine-oil like smell. It did certainly dry clear and created a slightly shiny finish on the plants, almost like a varnish. I am certainly curious to see how the roses turn out come spring.

    I think in the long run, another option when I think about 'winterising' roses is simply choosing roses that are truly hardy to my area. Double Scotch Pink, Doorenbos, Polareis and Therese Bugnet are certainly tempting me being listed as zone 2... I just like browsing http://www.cornhillnursery.com/retail/roses/roses.html

    This post was edited by prairie_northrose on Wed, Dec 17, 14 at 20:50

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