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The Lawn Review: Home » How To Prune Knock Out Roses: 2023 Guide

How To Prune Knock Out Roses: 2023 Guide

Pruning roses is not only a metaphor for the many difficulties of life, but also a necessary task to keep those babies coming back every year. Roses are an essential part of every garden and every episode of The Bachelor. 

They have a long-standing tradition of being the centerpiece of every backyard, so naturally, after some time has passed, they are considered an institution. But, there is a trick to keeping them lush and beautiful. It all comes down to how you prune them.

Taking pride in some knockout roses in your garden will make you feel like you are sitting on top of the world. To achieve that, you should know how to properly groom them, and do this every year so you can get the most out of them. Keep on reading and find out how to take care of your roses.

Jump ahead:

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How to prune a rose (especially a Knockout rose)

Here are the steps to prune roses:

  1. Look for a wilting rose
  2. Find the first set of 5-leaves from the bloom
  3. Prune at a 45-degree angle an inch above the 5-leaf set
  4. Repeat the process shaping the bush, removing dead stems
  5. Remove other branches to improve airflow 
  6. Don’t remove more than ⅓ of the size of the bush

The basics of rose pruning

The knockout rose bushes are incredible, and they grow very fast! Once you start dealing with them, you should know that they must be pruned yearly. By doing this, you will create some wonderful bushes, and get the best roses that aren’t just visually appealing, but super healthy.

pruning knockout roses
Don’t you just love it?

First, you should know that roses are extremely persistent, even in the coldest of weather. They can thrive even under temperatures below zero. It is the main reason why they are so popular – you can find them in any garden. They can easily adapt, and they look wonderful.

They are also extremely welcomed by spouses – especially if you’re in the dog house.

Best time to prune rose bushes

The best time in the year to prune roses is late winter or early spring. In other words, once you start noticing that your knockout rose has a few new shoots, it is time to start pruning. Make sure that the frost is over, and you are good to go!

As soon as the bush reaches 4 feet in height and 4 feet in width, you can trim it. Think of it as a ritual that you should do every year. Thinking about when to prune your rose bushes? Well, if you are hesitating, think of it this way – you need to measure the bush every once in a while

rose pruning guide
They bloom several times per year.

Don’t get us wrong, you can trim your rose bushes in the fall too, but if you want the best results, then early spring is the right time. This way, you will get better blooms.

How to prune knockout rose bushes – step by step

There are some specific bits of equipment you need whenever you want to groom your rose bushes. 

Step 1: Gather your tools

First of all, you will need hand pruners, then you will need hedge shears, and of course, gardening gloves so you can protect yourself during the process. Remember that you should disinfect the tools before you cut back the bushes. You can do this with alcohol (probably not beer, though).

preparation for pruning roses
These are the things you need!

Once you step into your garden, you might end up being amazed by the view – your knockout rose bush has tripled in size! This is only natural, since these roses grow large and fast.

Step 2: Get rid of the dead branches first

Start the process by removing the cross branches from the bushes. Look carefully. Do you see any weak, extremely thin, or maybe even diseased or dead branches? Start by cutting them right off. What you want to focus on is creating some thick and strong branches on your knockout rose bushes.

dead rose bush branches
Dead branches are easy to spot.

Step 3: Identify the wilted roses

Look for ones that are starting to wilt or completely wilted. Easy targets.

wilted roses
Pull the stem out a bit.

Step 4: Find the first set of five leaves from the flower

Once you have identified a wilted rose, work down the stem and count the leaves. When you have reached a set of five leaves, get your pruners ready.

first set of five leaves for pruning roses
Five leaves around the stem.

Step 5: Cut about an inch above the first set of five leaves

The first set of five leaves is a great landmark because it highlights a healthy area for the next bloom to sprout from. If you just pull the head of the rose off, it may not grow back because the stem immediately beneath it may be dying as well.

where to prune a rose
One inch above, at a 45 degree angle.

Step 6: Repeat the process, ensuring proper aeration of the bush as well

Continue to use the first set of five leaves as a landmark for pruning more roses. After you’ve completely pruned the roses and the dead branches, ensure there is proper airflow to the base of the rose bush.

pruning the entire rose bush
Get the whole thing!

Key tips while pruning a rose bush

To go a little deeper on the last step, always make sure that there is enough air circulating the knockout rose. 

What do we mean by this? 

The inside of the rose bush should be aerated at all times. So, when you start pruning, make sure to create an open space within the bush too. By practicing this, you will help the knockout rose bush avoid some serious diseases.

As soon as you start pruning, don’t be afraid to go all in! Cut back as much as you can! The knockout rose will grow back and look glorious, so don’t be afraid to cut off all extra branches.

Keep your tools sharp and clean

There are several aspects to this. First, by keeping your tools sharp, you will decrease the time you need to prune the bush. It will not take you hours to do that because your tools will work perfectly. Second (and more importantly), when you make a clean cut, it is also better for the rose. Instead of butchering it each time you cut a branch, making a clean cut will help the knockout rose heal faster.

Cut the branches at a 45-degree angle

If you want to promote fast and new growth of your rose bushes, the best way to prune them is to use this technique. Why cut them at this angle? Creating an angled cut will help the water run off the stem and reduce the chance of fungal rot.

How to know where to cut the branches? The ideal spot is located right above the first set of five leaves. If you are uncertain of where to cut the branches and want to avoid cutting here, there, and everywhere, then this is the best advice you can get.

Refrain from fertilizing your rose bush right after pruning.

Give it some time to heal before you add the fertilizer. The specific rose fertilizer has a high potassium level, which is important to keep an eye on so you can give your bushes everything they need to grow tall and strong.

If you’re looking for something more organic, mulched leaves work really well as an alternative to things like Miracle-Gro!

Why we prune roses: the bottom line

Pruning is a vital step in the process of maintaining a knockout rose bush healthy and strong. It does more than encourage the growth of healthy stems. It makes the plant produce more flowers, and it keeps disease and infections at bay. For successful pruning, all you need to do is follow the tips we have laid out for you. When it is time to prune, review them and get to work!

A final note – even if you over-prune the rose bush, it will grow back strong.

If you have some more questions, we can answer all of them! Take a look at our YouTube channel and get all the info you need!


Alex K

Alex is a lawn tool enthusiast who cut his teeth as a normal Joe lawn dad. After burning through expensive, fancy tools, Alex became dedicated to finding the best tools on the planet. He is now a leading expert on electric lawn tools, quoted in the Washington Post among other publications.