As I sit here on a chilly November day looking at the changing leaves, it has me thinking about the coming winter.
With winter approaching, we are nearing the time to winterize rose gardens here in the Midwest. Getting your roses prepared for winter can be the difference between having a perennial or annual rose garden. There are not likely many rose gardens that thrive year after year that aren’t properly winterized each year to ensure the best results for the following year.
The simplest method I have found for getting your roses ready to survive the winter is to cut them back and mound each bush up about 10-12 inches deep with mulch or compost. Once these important steps are taken, it is helpful to spray a fungicide to aid the roses into dormancy and to kill residual fungus that exist in and around the plant.
Sounds easy, right? Keep reading and I will break it down a little for you.
Why do I need to winterize my roses?
Winterizing your roses protects them against harsh winds and freezing temperatures. Cutting back long canes also helps them to be more protected from being broken and damaged from high gusts of winds.
Think of the process of winterizing like putting a small child to bed at night. If you put on a fresh diaper, clean jammies and tuck them in, then there is a much better chance that they will sleep soundly throughout the night. It’s the same thing with your roses. If you cut them back, mound them up and apply a fungicide, they will likely sleep much more soundly throughout the winter and come back strong in the spring and the many years to come.
When is the best time to start winterizing?
Typically, the best time to winterize your roses is close to Thanksgiving. Pruning your roses promotes new and continued growth. If you cut your roses back too early in the fall, it can promote growth if the temperatures get warm again. If this happens, this new growth can pull more growth hormone and moisture from the roots and soil. Once the temperatures drop below 32⁰, it will likely freeze those moist, growing canes and they will die back more than they would have otherwise.
Of course, this is the rule, but there can be exceptions. It’s important to know that you can always cut roses back too early, but not too late.
How short do I cut my roses back?
I have had good results by cutting hybrid teas, floribundas, and grandifloras back to about 18” or knee high. As earlier stated, leaving tall canes leaves them susceptible to being broken by harsh winds.
I like to leave climbers alone as much as I can when the canes are supported or are hearty enough to stay vertical. Any canes that are not supported or are horizontal can be cut back to where they can easily remain vertical.
My general rule of thumb for shrub roses, such as knockouts, fairy roses, miniatures, and others are to cut them down to about 50% of their current height. For example, if a knock out is 4’ tall, then I will cut it down to about 2’. In some cases, when the shrub is fairly small and I don’t plan on replacing it, I will not prune it back at all.
Rugosa roses do not need to be cut back for the winter.
Do all roses need to be winterized?
Outside of rugosa roses, I winterize all the other aforementioned rose bushes. If you choose to gamble with not protecting your roses for the winter, you may have some or all your roses survive the winter.
But this can be a very risky gamble that will likely not pay off in the end. Even if a rose survives the winter without protection, it could have a very slow start in the spring and may never fully recover in terms of gaining back its previously hearty growth.
Chances are good that many or all your roses will not come back in the spring. With the retail price of roses generally running from $30-$45 each, not protecting your roses for the winter can make them pretty expensive annuals.
How do you mound roses?
Before getting into the “how”, I want to mention a vital step that should be taken when planting your roses. It is very important that your rose’s bud union is planted 2-3 inches below the soil line. If your rose needs to be cut down close to the ground in the spring, you have a much better chance of your rose coming back.
Mounding your roses is a pretty simple task. As earlier mentioned, there are a few different materials and methods that can be used to accomplish this task.
It is also worth mentioning that you don’t want to cover your roses too early. Covering your roses doesn’t just protect them from the harsh winter winds, but it’s also important to keep them cold once they are cold. This helps them to go dormant and stay dormant until spring and warmer weather arrives.
First, let’s talk about some methods. The most common method is simply piling up mulch or compost at the base of the plant. The mulch method is typically done by collecting mulch from beds around your yard. Just grab a wheel barrow and a shovel and get to work.
You need to have enough to pile it 10-12 inches high on each rose. Once collected, use a shovel or pitch fork and drop a couple of scoops around the base of the rose. Make sure that the entire base of the rose is covered, not just the middle. Repeat this on all your roses.
I prefer to use mushroom compost, as it does a great job of insulating the rose, plus it provides nutrients to your garden. Whenever possible, make sure that the landscape materials supplier has a nice, finely shredded compost that is free from trash and rocks. This will be spread out in the rose bed in the spring and you don’t want to have to pull garbage and rocks out.
Depending on how many roses you have, you can either pick up the compost using a truck or trailer, or have it delivered by the supplier or your landscape company. Once you have the compost, follow the steps in the previous paragraph.
There are some more complicated methods of covering roses. Some still involve using mulch or compost. These are the “coning methods”. I have not used any coning methods yet, but likely will for a couple of customers that have unique situations. You can purchase Styrofoam rose cones for each rose. This can get pretty expensive if you have a lot of roses. They run anywhere between $5-$20 each.
The DIY rose cone can be constructed by getting some 24” wood stakes to make the 4 corners. Then wrap them in chicken wire by stapling it to each stake. Follow the chicken wire up by wrapping in burlap or something comparable. Once you have your cone constructed, drive it into the ground 8-12 inches and fill it about 8-12 inches with mulch or compost. If you are in an extremely cold winter place, you may want to fill the cone up higher.
Is any maintenance needed between winterizing and spring time?
Once you have cut back your roses, covered them and sprayed them with a fungicide, leave them alone until spring. No other maintenance is required. Just sit back, enjoy the winter and dream about the beautiful roses that your perfectly winterized garden will produce around Memorial Day.
When is the best time to uncover my roses in the spring?
The best time to uncover your roses in the spring is usually sometime in April. It is imperative to wait until the freezing temperatures are gone. I typically like to wait until the 14 day forecast calls for lows above 45⁰. Typically, the forecast won’t miss too bad on the low prediction. This way, even if it ends up being a bit colder that the 45⁰ forecast, you should be okay. If you uncover your roses too early and the new growth gets hit with a frost, it can kill your rose or severely delay the bloom cycle.
Remember, patience is a virtue! Be patient with your roses in the spring. You won’t be sorry.
I will write a post about uncovering your roses before spring comes. Fear not!
Have more questions?