Over the past few years, many parts of Texas, particularly Houston, have unexpectedly experienced the winter wonderland type weather. Snow and freeze are not common here, but so far we've experienced them more often than expected.
It's normal if you're concerned about your roses - especially if you are new to growing roses. In this blog post, I'll be sharing a few things I've learned through the last 2 rounds of freeze back in Feb 2021 and Dec 2022. Soon, we'll face another freeze in Jan 2024 (as low as 24F).
Great news is that roses are cold loving plants (not so much with the hot weather, you will see roses struggling more during our summer months).
With the drought and extra hot summer months we had these past few years, this cold weather brings a much needed relief for our roses. So take a step back and relax :)
First thing first, no need to cover your roses even if it snows. They do not have to be protected like tropical plants. Roses love cold weather and snow can act as an insulate to keep them warm. Crazy but true! Rose Gardeners up north don't cover theirs.
When people say - there is no need to do anything. I found that roses planted in the ground tend to be okay, but not necessary for roses in pots, very small/young roses, roses that struggle during summer months, and grafted roses.
So let's talk about it on a case by case basis:
*Very young/ownroot roses (particularly your own root that you just bought a few months ago), still in a nursery pot, you haven't planted it in the ground - you may keep it in a garage just in case. Otherwise when the temp is above freezing, your roses will be okay (unless they're weak or something is wrong to begin with).
I have 80% of my roses in pots. Roses are generally safer in the ground during extremely cold and hot weather.
"Potted roses" are a tad bit trickier. Temperature inside a pot is much lower than those in-ground in case they sit on a concrete floor during freeze or snow.
I lost some potted roses to the 2021 & 2022 freeze. What I realized was they were weak from drought & extreme heat during summertime. If yours are struggling, move them to your garage or cover if you can because these are fragile.
Otherwise, the healthy ones can take the cold/freeze/snow like champs
If you have potted roses like me and we end up getting freeze/snow, try to move them off your concrete floor so they sit directly on the grass or soil. Also mulch your potted roses to keep them warm and cozy.
Grafted roses tend to be more sensitive especially when grown in pots during hot summer and super cold winter. The ones planted in the ground may not be impacted as much by the cold/freeze.
Depending how deep or shallow you buried the bud union when planting, this may help determine whether you should put the mulch around them or not in preparation of the freeze/snow.
If the bud union is at the soil level or slightly underneath, you may or may not put mulch around the base
If the bud union is ABOVE the soil level: definitely cover the bud union to keep it warm.
As soon as the temperature is above freezing, spread those mulch away from the middle of the plant to give your rose room to breathe.
*If your roses struggled this past summer and are barely recovering:
I'm speaking from my experience with my roses that struggled in the summer of 2021 and 2022 and they barely recovered from drought and heat. Both summers were brutal to many of my potted roses, they were very weak. When the freeze hit, they couldn't handle another extreme weather it seemed. In this case, it was not the freeze/show that killed the roses, they were already weak/sick during the summer months.
Please note that if your roses recover just fine after this past summer, there is no need to worry about them. Freeze and snow will help roses bloom beautifully in the springtime. Similar to apples, that type of chill hours helps produce big and gorgeous blooms.
If you have struggling roses, I highly recommend moving them to your garage if you can (if they are in pots. If they are in the ground, DO NOT dig them up to put in a pot, just mulch to provide extra warmth).
Left: Plum Perfect under 1 year old | Right: Koko Loko under 1 year old during the 2021 freeze
Let's talk about what to do in the fall in preparation of unexpected freeze/snow
1) Stop deadheading/cutting flowers: when you deadhead/cut your roses during active growing seasons, it signals your roses to make more flowers (which is fantastic because we want them to be making more flowers for us to enjoy).
However when it gets close to the winter months, it's a great idea for roses to reserve their energy and go dormant (rest/sleep during winter) so they can be well rested and become even more robust & glorious in spring.
In order to make flowers, roses use a lot of energy to produce and bloom. Producing flowers and putting on new growths during an extreme weather (either too hot or below freezing temp) can potentially put their health at risk. Think of our body when we expose to freeze or snow, we want to reserve as much energy as possible in order to survive. The same goes with roses. They need their energy to survive cold months as well.
Cold weather (above freezing) usually doesn't cause any concern as roses like and can tolerate cold weather...even snow. Flowers also open up much slower and last longer on the plant. You just have to remind yourself NOT to deadhead (which is so tempting for me as I like to cut and bring flowers inside!)
Last year, I stopped deadheading and cutting in December. However, with this usually cold weather, I personally stopped all activities sooner just in case and just let the rest of the buds to develop, open and shatter in their own time. Just look, admire and absorb their beauties. So hard to resist a temptation to cut - that sounds like a personal issue, doesn't it?!?
2) Stop trimming/pruning and fertilizing: the same reasons as mentioned above. If we end up getting freeze or snowing, that kind of temperature will kill off new growths or buds anyway. This is why you don't want to encourage new growth/flowers during this time.
If the new growths or buds are already there, just leave them be. Mother nature will take care of it. Let nature go through its course.
3) Plant new roses or move existing roses (as long as the ground is not frozen): Fall is a fantastic time to move things around especially if you've been thinking about moving certain roses to their new spots.
Our temperature generally doesn't get below a freezing point or the ground is covered with snow.
Therefore, it's safe to plant or move. Replanting during this time can reduce transplant shock as well compared to moving them during hot months.
If you have roses that have been in their nursery pots for months, this is also the time you can plant them in the ground.
Alternatively for your brand new small own root or band roses (baby roses) that are still very tender and young and you don't want to take a chance in case there's a freeze or snow, you may keep them in a pot (try to get a new pot instead of leaving in a nursery pot as those nursery pots are so thin and whimsy. This pot is what I use to keep my young roses in until they grow bigger.
4) Mulch: mulching acts like a blanket for roses during winter. I don't normally mulch unless we expect to have a freeze or snow. You can put on a thick layer of mulch around the base of your rose to help keep them warm.
**Clean up the base of your roses before you spread mulch as well. Pick up fallen/diseased leaves and remove them from your garden if you can.
5) Water if necessary: usually during winter, we get occasional rain so we don't really need to water. The only exception is if we don't get any rain, the ground is so dry and it's expected to be below freezing, watering is necessary for both potted and in-ground roses in order to keep the roots hydrated.
Watering is especially important for potted roses as temp inside your pots tend to be lower than in-ground roses.
**Do not overwater or water too frequently though. They don't need as much water as they do in warmer months. Once a week may be enough depending how dry the soil is. Just enough to keep them moist to prepare for snow or freeze.
Plum Perfect and Koko Loko in 2022
Love Song rose in Dec 2022 > April 2023
Do I need to treat blackspots, other diseases or pests in the fall?
I wouldn't worry about it as the growing season is coming to an end. Some old leaves will fall off. Your roses may start having more blackspots than usual now or soon - but it's their normal cycle as they'll be shredding those old leaves in the months to come. Some may not lose their leaves while some may go naked.
You can resume your preventative regimen/schedule again early spring.
Snow and freeze are not something we expect to get every year in our climate, but it sure can happen given a few unexpected snow days we had over the past few years.
However, you can rest assured that your roses will be okay. Their flowers may make you think they are such delicate little plants. In reality, they are not. They are tough beauties. Roses are incredibly tough and resilient. Cold weather will help them become even more robust and glorious in springtime so embrace the cold :)