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Roses are amongst the most sought-after and most reviled landscape shrubs. Many gardeners love them for their irascible nature and beautiful blooms, but there are just as many who wish they’d never planted them in the first place. This article is for the latter.
The most effective ways to kill a stubborn rose bush so that it never comes back are:
- Starving it to death
- Cutting back to the crown repeatedly
- Digging up the root ball
- Cutting the canes and covering the crown until root death
- Application of an herbicide
- Using mechanical methods like goats or mowing
So pull on your rose gauntlets, pick up your hand saw, and let’s get this started.
Starve it out
A weakened rose is much easier to remove than a healthy, robust rose.
If you know that you’re going to remove a rose bush in the near or distant future, begin now by cutting off its water supply and making sure it doesn’t receive any fertilizer.
If you starve it for long enough and you live in a harsher climate where water and nutrients are scarce, this might be enough to kill a rose bush.
But roses are very resilient shrubs, so in milder climates where soil is rich and precipitation occurs more often, it’s unlikely that this alone will be enough to kill it.
It will, however, significantly tax the root system and affect the health of the plant, making it more vulnerable to insect and disease attacks, which will weaken it further.
Cut it back severely
Cutting the rose back to the crown multiple times will trigger the rose to send out new canes as many times as they are cut back. This means that the roots direct their resources to that new upward growth, instead of new root growth. Over time, this will weaken the roots and make them easier to remove or kill.
Additionally, topping a rose bush like this will remove all the leaves, cutting off the plant’s ability to photosynthesize and make the sugars it needs to survive. Eventually, a rose crown with no canes and no leaves will die without being dug up–you just need to keep on top of trimming back new growth.
And reducing the size of the rose will also make it much easier for you to handle the plant and kill the root ball to prevent any new growth, which is your ultimate goal. This is particularly true when you are trying to kill a climbing rose, whose canes can be ten feet long, or get rid of a shrub rose, which can be five feet tall and wide.
Dig up the roots
While it may be labor-intensive, this method is also very reliable, as it completely removes the bush, its roots, and any potential future regrowth from the crown. Digging up the roots permanently kills a rose bush.
The day before you plan to dig, cut the rose back to the ground and water around it thoroughly on all sides–this will soften the soil and make digging easier.
Use a pointed shovel to slice into the ground around the rose, outlining a rough circle shape. The roots may extend as far out as three feet, but twelve inches out from the crown is usually adequate.
Then, sink your shovel in deep and lever the root ball out of the ground. You may need to do this in sections, and you may need to use the shovel to cut through the large feeder roots that keep the crown anchored.
Cut and cover the crown
This method takes time and patience, but is highly effective and needs no shovels, no spades, and no chemical herbicides. This is one of the best non-synthetic-chemical methods to kill a rose bush, and is also ideal for gardeners who aren’t quite up to digging an entire root ball out of the ground.
This is how to kill a rose bush without digging it up: first, cut the canes of the rose hard back to the crown, then cover the stump with an opaque tarp or several layers of cardboard. Use bricks or large rocks to prevent the cover from blowing away in any strong winds!
Keep the cover on for a year, or at least a full growing season. This will keep light from reaching the crown and any new shoots that it sends up, slowly starving it out. The damp, dark conditions under the cover will also attract insects and microorganisms, accelerating the rate of decay as the root starts to die.
You can speed things along by occasionally uncovering the stump and pruning out any new growth. This will steal even more energy from the remaining roots.
This is also an excellent method in combination with the dig-out approach. Covering the crown will go a long way towards killing the rose bush at the root, making your job easier when you go in to dig it out completely.
Apply an herbicide
Herbicides should be selected and used with care, but they can be very effective killers of rose bushes without all the elbow grease.
Read the label of your chosen herbicide carefully for application instructions, dosage, storage, and disposal.
Most herbicides work best when applied in the spring when the phloem in the rose is moving and can transport the herbicide deep into its tissues.
Use a separate sprayer, bucket, or other tools to mix and apply the herbicide. You’ll also want to wait a few weeks before planting anything else in the place where the rose once was.
Never use more herbicide than the instructions indicate, and always wear protective gear–long sleeves and pants, closed-toed shoes, gloves, and eye protection. Because herbicides are absorbed through cells, they can easily penetrate the human body, especially through the groin and eye area (source). So make sure to wash your hands thoroughly after you apply any product to your rose.
Whenever you apply an herbicide, it’s best to do so on a cool, rain-free, non-windy day. This ensures maximum efficacy of the herbicide, and avoids the issue of rain washing the chemical away before it can do its work on the rose bush, or a breeze blowing the chemical onto you as you apply it.
Two of the best stump and brush eradicators that also work great to kill roots of a rose bush are Spectracide Stump Remover, and Fertilome Brush and Stump Killer (each of these is a link to Amazon). These are painted onto the cut-back crown of the rose in order to kill the stump and root ball.
Will Roundup kill a rose bush? Absolutely! You will need to dilute it in a solution and spray it onto the canes and foliage, and you might need to apply it two or more times to completely kill the rose.
All of these herbicides are non-selective, meaning that they kill whatever plant they come in contact with. So it’s important that you be precise with the substance as you apply it, to make sure that you only kill the pesky rose bush instead of the beautiful shrub or tree growing right beside it.
If your water table is high or the rose bush in question is next to a stream or pond, consider physical removal instead. Chemical herbicides and pesticides can cause major problems if they enter a watershed, including die-off of beneficial plants and poisoning local fish, amphibian, reptile, and mammal populations (source).
Rent a goat
You read that right. Goats are the garbage disposals of the animal husbandry world, well-known for their relish for plants that other grazers like sheep or cattle would avoid, such as poison ivy, Canadian thistle, and, indeed, roses.
This is an especially good option to knock back large stands of multiflora rose: the wild, brambly, impossible-to-control sister of hybrid tea and landscape roses. Aside from grazing the roses to the ground, the goats will also eat many of the weeds in the same area, which contributes to wildfire fuel reduction. Goat grazing can be an important and useful means of fuel reduction and weed control if you live on a large acreage or in wildfire country.
Goats are growing in popularity as a mechanical weed control for invasive species, so check out these sites for listings of goat herds for rent in your area:
Using goats will reduce your problem roses down to the ground, and you can then finish them off by digging up the roots, applying an herbicide to the crown, or covering the crown. Or, you can bring in goats on a regular basis to keep the roses (and other weeds) under control.
If goats are not available in your area and you do have large stands of multiflora or wild roses, you can mimic their effect through repeated mowing of the area.
Things you should NOT use to kill a rose bush
Rock salt and Epsom salt
Rock salt and epsom salt are sometimes recommended as natural, chemical-free weed killers, but these terms are very misleading, and using any kind of salt as an herbicide in your garden will almost certainly kill off more plants than you want to.
For one thing, these substances are, by default, chemicals. They may not be synthetic chemicals, but they are still produced by a chemical process. This means that overuse, misuse, or mishandling of these substances can cause as much damage to your or your yard as a synthetic chemical with a hazard label can.
Salt is sodium chloride, the combination of the two elements sodium and chlorine. The idea behind using it as a plant-killer is that these elements poison plant tissues, while also drawing the moisture out of the plant, fatally dehydrating it.
All well and good, until you consider the fact that these plant-killing elements are now tied up in your soil, binding up the nutrients your plants need and decreasing the soil’s ability to retain water (source).
Excess salt buildup in soils can result in:
- Displacement of vital nutrient potassium by salt ion
- Water stress
- Accumulation of toxic chloride buildup
- Increased soil impaction
- Nutrient deficiency
If you use rock salt or Epsom salt to try and kill a rose bush, you may in fact poison your soil and make it unable to support plant life.
Bleach and Vinegar
Two more entries in the ranks of do-it-yourself weed killers are bleach and agricultural vinegar. Both are highly dangerous to gardeners and their desirable plants, along with the insect and microbial life of the soil they come in contact with.
Bleach, like salt, contains chlorine, which is toxic to plant tissues and can build up in the soil long after your targeted rose is gone.
Meanwhile, agricultural vinegar is 10% (or more) acetic acid, which burns whatever it comes in contact with. This could mean your stubborn rose bush–but it could also be your prized agapanthus right beside it, or your skin, or even your eyes if they are exposed to fumes (source).
Additionally, both bleach and vinegar will kill any insect and beneficial microbe life they encounter in the soil–earthworms, mycorrhizae, growth-promoting rhizobacteria, and nitrogen-fixing cyanobacteria will all be destroyed on contact. Meanwhile, the roots of the rose will not be affected!
In the long run, introducing these substances into your garden will damage the soil and have a long-term effect on its ability to support other, non-rose plant life.
For more detail on common “natural” weed killers, check out Thriving Yard’s article devoted to the subject here.
Fire
While arborists sometimes use fire to break down large tree stumps, this is a bad idea for homeowners to use on their roses–even if they really would like to set them on fire.
Burning out a stump involves drilling holes into it, packing them with an accelerant, using hot water to spread the accelerant through the tissues of the stump to increase its flammability, and then starting a fire on top of it.
Generally speaking, a rose crown will never be large enough to warrant something like this.
It is also significantly hazardous, as a controlled burn can quickly become an uncontrolled burn that can damage other plants in your garden, structures on your property (including your house!), your own personal safety, and structures around you.
For more information on these hazards, read Should We Burn Yard Waste? Brush Burning Safety & Alternatives.
How to dispose of a dead rose bush
Instead of composting, it’s safer to throw away or burn a dead or uprooted rose bush. Bacteria and disease in the cell tissue of roses could inoculate your compost with something yucky, and their sharp thorns resist breakdown.
Roses are notorious re-growers, particularly the wild multiflora rose, and if placed in your compost or green waste heap they may be able to resurrect themselves.
Additionally, roses are very vulnerable to fungus, bacteria, and diseases, and most roses will contract one or all of these during their lifetime. These afflictions are usually evident by black or reddish discoloration on stems, galls or cankers, or malformed flowers and flower buds.
As a species roses have resistance to these diseases and are able to survive in spite of them, but other plants lack their unkillable hardiness. Like any other diseased plant tissue, it’s best to keep it out of your compost.
Conclusion
Thriving Yard has a lot of articles on how to keep your plants alive. But sometimes, with some plants, you need a way to kill them and make sure they stay dead.
Remember, to kill a rose bush, you will need to both remove the top of the bush and either dig up or otherwise kill the roots. It is helpful to weaken the bush beforehand by withholding water and fertilizer. You’ll need to combine mechanical and chemical methods in order to completely eradicate a rose, and it may take more than one season and more than one method.