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When And How To Prune Knock Out Roses For Abundant Flowers

When And How To Prune Knock Out Roses For Abundant Flowers

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It’s in the knock out roses’ nature to be tough and easy to maintain. Yet, even these shrubs need some trimming if you want them to reach their full glory.

They will produce a profusion of flowers and grow quite fast if you care for them the right way. Luckily, their needs are a bit easier to follow compared to other rose varieties.

That’s why gardeners love them! Here’s how to prune them in order to get the most out of them!

Let’s get started!

Tools You’ll Need

Pruners are one of the essential houseplants tools every gardener needs. They are the first tool in your kit you’ll need for trimming chores.

You might want to add loppers for thicker branches, and throw on some gloves to protect your hands from thorny shoots.

Make sure your garden shears and loppers are sharp and disinfected so that you don’t transfer diseases all over your garden!

When To Prune Knock Out Roses

These shrubs bloom on new wood, so the best time to trim them is before they start pushing out new stems. This practice will encourage your bush to produce more new growth, which will bear most of that season’s flowers.

Ideally, you’d want to cut back your knock out roses in late winter or at the beginning of spring, right when you start to see some new growth, but not too much.

Wait until you see a couple of tiny new red buds appearing on stems, take your pruners and loppers, and start chopping. New growth is a sign that your plant is waking up and will produce new shoots in no time.

The exact pruning time depends on your region. If you live in the South, you’ll want to trim your roses around mid-February. In the northern USDA zones, the growth resumes sometimes in March, so it’s best to wait until then.

These colder months are perfect for hard pruning, but what about light pruning? You can conduct it in summer, but make sure not to remove too much.

What I love about knock outs is that they don’t need deadheading. They will self-clean, but you can still help them out if you want your bush to look cleaner and healthier in no time!

Just know when to stop! Don’t prune your knock outs after late summer and fall.

How To Cut Them Back

One of the most common rose growing mistakes is improper pruning. First, take a good look at your bush and plan everything out. I’m talking about the size and shape you want to go for. Then put on your pruning gloves on and get to work!

When pruning knock outs, the first thing you want to get rid of is everything that’s dead, diseased, or damaged. Pruning when those red shoots appear will help you distinguish between dead and alive branches.

The next step is to remove all the stems that are growing in unwanted directions. I’m talking about the ones that cross, grow towards the center, or are weak and curvy. Trim them all the way back to where they join the main branch.

This practice will introduce more airflow and sunlight to your rose bush. It will reduce the risk of fungal diseases and ensure even the darkest, innermost parts of the shrub get some light.

Then, divert your eyes to the base of the plant. Look for the ancient, thick, and gray branches. Prune a third of them to about 4 inches from the soil surface.

Only after you do all this can you start thinking about downsizing your knock out rose shrub. You can remove up to a third or just an eighth of the entire bush. It’s up to you!

Bear in mind that knock out roses are avid growers and will triple in size during their waking seasons. Think about how much they can grow in the upcoming months so that they don’t clash with other plants.

And if you haven’t pruned your knock outs in ages, then you can try a rejuvenation option. Cut an entire bush to about 6-8 inches from the ground. It may sound harsh, but this vigorous grower will recover in no time and produce new stems before you know it!

Should You Snip Knock Out Rose Stems In Fall?

DO NOT cut your knock out roses back in fall. It is one of the common mistakes that can cause severe damage to your bush.


Because pruning encourages new growth. Cutting this shrub back late in the season, just before the cold months arrive, will cause it to produce delicate new canes. 

They will freeze, die, and put your entire rose shrub at risk of pest infestations and disease infections.

Can You Do This Chore In Summer?

If you love landscaping with knock out roses, then you should know that you can give these shrubs a light prune come summer.

The main pruning chore at this time is deadheading. As I already mentioned, the knock outs will self-clean, but there’s no harm in helping them out.

In fact, you’ll encourage your shrub to set new buds and produce more blossoms sooner than they normally would! Trim individual flowers or remove entire clusters.

You should also remove any canes with signs of disease or damage. This will keep your knock out roses healthy and thriving.