What’s the Deal with Dormancy? A Rose Story

Dormancy is nature’s way of making sure that roses see next spring by preventing damage from freezing temperatures. Inside the stems, cell sap will thicken making the plant additionally cold hardy and capable of withstanding long winters. The rose will then go into a hibernation-type state where it will slow down its metabolic systems, and reserve vital nutrients to flush out when fair weather returns in spring.

This is very similar to the way that dormancy works in other plants, such as hydrangeas or Crape Myrtles. However, the shocking truth is that most modern day roses do not go dormant! In fact, the only roses that truly go dormant are non-reblooming Old Garden Roses. Modern re-blooming roses are designed to continuously restart their growth cycle for repeat blooming. For this reason, they do not get to a point where they are actually in dormancy.

Word on the Street

There’s a lot of different advice out there regarding the proper way to prepare your roses for winter and we’re going to go through a couple.

Some say it’s key to stop fertilizing before the cold weather to discourage further new growth before freezing temperatures. This seems like it would make sense, however, nature is a bit too smart to make this mistake, and roses will not absorb fertilizer below a certain temperature. Re-blooming roses will still flush out after an extended period above freezing temperatures, regardless of whether they have been fertilized. It’s still a good idea not to fertilize shortly before the onset of cold weather, though, because it will simply be a waste of perfectly good fertilizer.

Another misconception involves allowing blooms to age and develop hips. The misunderstanding here comes from the fact that roses traditionally would go dormant after producing seeds. However, hip production is just another stage of growth and they aren’t actually gearing down for winter. Since they’re designed to re-bloom perpetually, they will continue to grow even after hips are produced.

So What Can I Do?

The answer to this question lies in a couple different areas.

  • 1. Make sure your roses are appropriate for your USDA Zone

If your roses are cold hardy in your zone, you will usually be okay when spring rolls around.

  • 2. Understand your zone

Interestingly enough, colder zones are less dangerous to roses than zones with considerable temperature fluctuation. Consistently below-freezing temperatures allow roses to reserve their strength and flush out once spring returns. However, if you are in a zone that frequently experiences hard freezes and then thaws, you risk your roses freezing, flushing out, and then freezing again. This results in a higher plant mortality rate than a more consistent temperature range.

  • 3. Protect the base.                                                

Whether you have an own-root rose or a grafted rose, the base is the most important part to protect from the winter cold. Remove the decaying plant matter from around the base, add about a foot of soil (more or less depending on the size of the plant), cover the mound with a layer of straw or similar material, and top with a bit more soil. There are numerous ways to achieve this same effect. Some gardeners opt to use insulated construction tarps or blankets, and Styrofoam rose cones have gained popularity in recent years as well. However you do it, this precaution will help to ensure that your roses make it through the winter. Once the threat of frost is gone, gently remove the soil or covering.

The highly critical base of the rose serves as the epicenter for it's triumphant return in spring.


What’s Next?

Early spring is the ideal time to trim your roses back. First, remove any dead branches to avoid disease taking hold. Afterwards, proceed with pruning. Most modern re-blooming roses perform best after pruning 1/3 of the old wood each spring. This will allow for a hard flush and optimal blooming. Then just hit them with a fertilizer of your choice and they’re all ready for the new growing season.

I hope that this has provided you with some insight into the world of rose dormancy. Please contact us over here at PlantsByMail.com if you have any questions or comments, and stay planting out there!

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