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When Do You Cut Back Knock Out Roses

I have always loved roses, and when I shifted to a house with a garden, I was thrilled! I cleared a big patch and planted rose bushes. I waited for a couple of months, but nothing much happened!

The few roses that grew were of poor quality. However, I did not give up and kept trying with different varieties and used the best fertilizers, and yet the results were the same.

Finally, I gave up after working for more than a year. It was while visiting a friend that I noticed the profusion of colorful roses in his garden!! When I asked, he told me that these were Knock-out Roses!! They knocked me out and I am sure you want to know too when to cut back knock out roses.

What is Special about Knock out Roses?

Easy Care or Carefree roses are a part of most of the colorful landscapes. These are other names of knock out roses. They are such natural plants to grow and flower abundantly!

These are low-maintenance bushes and can grow on a variety of soils and in a variety of weather. Let us take a look at what makes these roses so unique!

  • First and foremost, it requires very less care and effort
  • No need to deadhead the bushes
  • They don’t need pesticides because they are naturally insect resistant.
  • They are also resistant to diseases like ‘Black Spot’
  • Both these factors make it ideal for an organic garden
  • They can grow in both partial shade and sunlight
  • They can grow in a variety of weather and temperatures
  • The flowering season continues for months at a time

They generally maintain a round and upright shape and are full of flowers. They can grow to a height of about 3 to 4 feet and also a width of about 3 feet. You should know that these can grow into big bushes if left to nature. They can almost resemble a tree at about 5 feet in length and nearly as wide!!

When Do You Cut Back Knock Out Roses?

Knockout roses have become very popular because of the belief that these are ‘no maintenance’ roses. It is correct to a large extent, but some people think there is no need to water, fertilize or prune!!

They feel that you have to stick it in some soil and it will start to bloom and flower!! Unfortunately, this is not correct. These roses do need some care, and that includes pruning.

The best time to prune all types of roses is either in late winters or in early spring. This is the time when new growth starts. Fall is not a good time for pruning, as this could lead to the death of the plant.

When it comes to cutting back a knockout rose plant, there are some things you should keep in mind. Knockout roses are very fast-growing, and you have to prune them timely.

  • A proper pruning technique is a must.
  • February is the best month for pruning
  • First, remove the deadheads and any broken branches
  • Open up the inside of the bush by removing dead or unproductive branches
  • Now trim the healthy branches by almost a third of their length
  • Shape the bushes by following the natural formations
  • You can prune once a year and then trim and cut when you feel the need

Proper Pruning

Knockout roses are such hardy plants that any way you prune, they survive and thrive! Many people complain that it grows fast and grows more significant than expected! You will have to decide how big you want the bush to be. This will depend on your garden and other plants.

  • If you want a large bush, then you should only do a light trim. Remove the deadwood and branches, but don’t cut too deep. This will result in thicker branches and lesser flowers.
  • You can prune the thick sticks close to the ground. This will give a chance to new canes to sprout. More flowers come on the latest and young branches.
  • If you want to keep the size down, you will have to prune more severely. You should follow the first two steps and then cut the remaining branches as well. By the time you finish, the plant will look like a bunch of sticks, but don’t worry; it will recover very soon.
  • If your plant is growing too fast, then stop fertilizing. Do it just once when you are pruning, and your plant will not only survive but thrive.
  • Some people prefer to do two pruning every year — first time in January when you should cut back by about half their height. The second time you should cut back at the end of August but not very severely. This time cut them back by only about one-third of the height.

Remember these points

  • You should wear heavy gloves because the plants have thorns.
  • Use a sharp pruner to do the job. You need to make clear cuts and not damage the stems.


After going through the information, we are sure that you have a clear idea of the pruning process. They are easy to care for, which makes them a part of many gardens.

You can make them a part of the landscape or plant them as hedges. In every way, they are a great addition to your garden. If you give the knockout roses a little bit of care, they will add a lot of beauty to your yard.

Pruning the plant at the right time and in the right way will keep it in the best shape and result in better flowering. Do get in touch with us if you need more information or have any suggestions for us.


Saturday 6th of November 2021

I live in Southeastern Wisconsin, February here is generally sno everywhere! so, when should I trim my knockout roses?

Hoang Quang

Wednesday 10th of November 2021

The right time to trim knockout roses is in early spring or late winter. This is when the new growth begins. Autumn is not the best time to cut as it can cause the plants to die. When trimming the healthy trim knockout roses, you can do it about a third of the length. Since these plants grow very quickly, they need to be cut promptly.

Enola Pickard

Sunday 3rd of October 2021

Can I prune diseased parts of my knockout roses now? It is early Oct in northeast texas - still warm. Trying to save them (rise rosette disease). Thank you

Hoang Quang

Sunday 10th of October 2021

Knock-out Roses are the most simple and easiest roses to grow and maintain. However, the time to cut back roses or prune can be solely dependent on the location you are in. In addition, this practice is majorly done twice a year. Let’s discuss the right time to prune or cut back your knock out roses;

Late winter Late winter serves to be the best time to prune or cut back your knock-out roses. Usually, these roses require little care and maintenance as they grow. You might find yourself neglecting them because they might grow independently without serious care done on them. Also if late winter caught you off guard and failed to perform the practice. You can also cut back or prune your roses very early in spring.

Cutting back your knock-out roses during these seasons might serve the following purposes. First, it will ensure your plants maintain a good and well-structured growing habit. Second, these seasons will help your roses to have more healthy blooms as they grow throughout the season. Therefore, you’re free to cut back your knock-out roses when the plant is dormant or immediately you see the new flowers start to grow.

So, at this particular time, cut the shrub back roughly to about twelve to eighteen inches above the ground. When cutting the shrubs, be certain that your cut appears just above a leaf bud facing outwardly. A leaf bud is typically a small leaf that will grow into a new branch or leaf, but not a thorn as some might presume. In most cases, pruning above a leaf bud facing outward enhance wider and bushier rose growth.

During summer Summer is also another pertinent season you can engage in pruning or cutting back on knock-out roses. That means; you can prune roses even during their active growing season. In this period, the dead blooms will re-bloom faster as the pruning process is initiated well. This type of rose normally experiences several bloom cycles throughout its growth journey. So, pruning will essentially ignite the growth of new bloom in the course of this growing season.

Therefore, you can primarily remove the deadheading blooms with an appropriate pruning tool at every stage of their bloom cycles. The deadheading blooms are removed from the base of the plant stem. Or an inch downward or above the first five leaflets. Generally, five leaflet leaves seem to be positioned where the can is somewhat thicker enough to anchor the next long stem flower that will grow from it.

Moreover, if you want your roses to maintain certain shapes, you can also cut back branches that have grown in an undesirable position. Also, feel free to remove damaged branches any time you feel like it. Similarly, after you are done with the late August or early September cutting back of roses. Ensure that you fertilize the bushes with an ideal fertilizer or use a rose fertilizer according to the label directions. It will help your flower to maintain a superb display during the autumn/fall blooming season.

On the flip side, sharp bypass hand pruners are the best pruning tool you can use when cutting back knock-out roses. These tools are the best because they minimize stem destruction and ensure a safe cut or pruning of roses. In addition, it is recommended to put on a sturdy pair of long sleeves and leather gloves. Roses contain thorns that might puncture you, scratch your arms, or cause blisters while pruning.

Similarly, there is no set formula on how you should cut back knock out roses or prune. The cutting depends solely on the desires and wishes of the gardener and the intent of pruning. Thus, if you desire your roses to grow tall and form a certain shape, you’ll be compelled to do lighter pruning and sniff out dead wood.

Georgene Miller

Thursday 2nd of September 2021

My knockout roses have some kind disease. The canes are turning black. They were sprayed twice for the spot fungus on the leaves. Should I cut them back now or wait till spring? Thank you.

Hoang Quang

Saturday 4th of September 2021

You need to wait until spring and also do the following: • Always water knockout roses in the morning, as the fungus only germinates after seven hours of constant exposure to moisture. • Use some organic and chemical treatments available, including some biological methods that you have already use elsewhere. • Spray one part milk to two parts water changes because it changes fungi pH, finally killing them. • Use neem oil, mainly when used in wet soil with foliar sprays to combat visible fungal outbreaks.

Marlene Sable

Wednesday 28th of April 2021

Quang. We have very large knockout rose bushes that were not pruned in February. Is it possible to cut them back now in May without damaging them? Thank you for all your information and timely tips.

Hoang Quang

Thursday 6th of May 2021

No, this is because during that time there is intense heat and they can be stressed up.

Kathleen Findlay

Sunday 8th of November 2020

Quang, I appreciate the valuable information regarding the pruning of the Knockout Roses. Does the February pruning also apply to those of us in Northwestern Pennsylvania? I'll reference your website per the links below for additional information pertaining to many other flowers. Again, thank you for sharing your expertise!