PlantsRoses→Rose (Rosa 'Double Knock Out')

Alternative cultivar names:
'Double Knock Out'
'RADtko'

Also sold as:
Double Knockout

Data specific to Roses (Edit)
Bloom size: Medium: 2-3"
Petal count: full: 26-40 petals
Rose bloom color: Medium red
Extra Bloom Info: In clusters
Rebloom: Good
Class: Shrub
Growth Habit: Medium, 3-4 feet, bushy
Fragrance: None
Hybridizer & year: William J. Radler, 2004
Optimal growing zones: USDA zone 4 and warmer

General Plant Information (Edit)
Plant Habit: Shrub
Life cycle: Perennial
Sun Requirements: Full Sun
Soil pH Preferences: Moderately acid (5.6 – 6.0)
Slightly acid (6.1 – 6.5)
Neutral (6.6 – 7.3)
Slightly alkaline (7.4 – 7.8)
Plant Height: 3-4 feet
Plant Spread: 2-3 feet
Leaves: Deciduous
Flowers: Showy
Flower Color: Red
Flower Time: Spring
Summer
Fall
Uses: Cut Flower
Wildlife Attractant: Bees
Propagation: Other methods: Cuttings: Stem
Cuttings: Tip
Miscellaneous: With thorns/spines/prickles/teeth
Awards and Recognitions: Texas Superstar®
Parentage: unnamed seedling x unnamed seedling
Child plants: 3 child plants

Easy Rose Plant

A Week of Celebrating RosesA Week of Celebrating Roses
By dave on April 25, 2015

It's Roses Celebration Week, a week we've been looking forward to all year! This week we'll encourage everyone to share their photos, comments and information about roses. Let's open the week with a look at the top cultivars, top comments, most thumbed images, and more!

(Full article7 comments)
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Photo gallery:
Location: My Garden in Janesville, WIDate: 2014-05-19
By tveguy3
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Location: Botanical Gardens of the State of Georgia...Athens, GaDate: 2019-04-17Knockout Rose 052
By dawiz1753
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Location: Botanical Gardens of the State of Georgia...Athens, GaDate: 2017-10-26Double Knockout Rose 001
By dawiz1753
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Image
By jim1961
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Image
By Salems
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Location: Central Pa.Date: August 2018Double Knockout rose
By jim1961
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Location: Willow Valley Communities Lakes Campus, Willow Street, Pennsylvania USADate: 2019-10-24Late season bloom
By csandt
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Location: Botanical Gardens of the State of Georgia...Athens, GaDate: 2019-09-22Red Knockout Rose With Dewdrops 070a
By dawiz1753
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Location: In my zone 8 gardenDate: 2017-03-20
By sarahbugw
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Location: My previous yard in Temple, TexasDate: 2013Prolific blooms every season before I moved.
By Peggy8b
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Location: Gause, TexasDate: 2020-06-093rd season in very sandy soil, Central TX.
By Peggy8b
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Location: Breezy Knees garden, York, UKDate: 2020-09-10
By kniphofia
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Location: Breezy Knees garden, York, UKDate: 2020-09-10
By kniphofia
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Image
By Debbie
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Location: Rose Garden Center, Tyler, TexasDate: 2014-05-03
By jon
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By stilldew
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Location: Botanical Gardens of the State of Georgia...Athens, GaDate: 2019-04-23Dew Covered Double Knockout Rose 008
By dawiz1753
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Location: Botanical Gardens of the State of Georgia...Athens, GaDate: 2019-06-23Double Knockout Rose 011
By dawiz1753
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Location: Sherwood OregonDate: 2020-05-14
By Toni
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Location: Gause, TexasDate: 2020-04-272-year plant finally taking off after a 2-year struggle with heat
By Peggy8b
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Location: Middle TennesseeDate: 2011-10-09Covered with dew in the morning
By SongofJoy
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Location: At my neighbor's house in Northern KYDate: 2012-04-22
By Marilyn
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Location: At my neighbor's house in Hebron, KYDate: 2012-04-22
By Marilyn
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Image
By stilldew
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Location: My Cincinnati Ohio gardenDate: 2013-06-22Recent additions to my yard
By kqcrna
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Location: Rose Garden Center, Tyler, TexasDate: 2014-05-03
By jon
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Location: Allentown, PennsylvaniaDate: 2015-05-30
By plantrob
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By Hamwild
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Date: 2018-04-22
By Hamwild
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Location: Grapevine, Texas USADate: April 17, 2020Planted Fall 2018
By LindsayG
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Location: Grapevine, Texas USADate: April 17, 2020Planted Fall 2018
By LindsayG
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Location: My garden, Cottage-in-the-Meadow Gardens in South Amana, IADate: 2013-06-08
By LarryR
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Location: Rose Garden Center, Tyler, TexasDate: 2014-05-03
By jon
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Location: Rose Garden Center, Tyler, TexasDate: 2014-05-03
By jon
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Location: Rose Garden Center, Tyler, TexasDate: 2014-05-03
By jon
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This plant is tagged in:
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Comments:
Posted by ssgardener (Silver Spring, MD - Zone 7a) on Mar 12, 2013 6:06 AM

I have this in afternoon sun, maybe 4-5 hours of direct sun. It blooms beautifully, right up until a hard freeze in November.

Last year the blooms were so heavy and numerous that they flopped over. I don't know whether it's related to not getting full sun, or my poor pruning job in the spring. No more flopping after that first very heavy flush of blooming.

This is truly a carefree rose. They got a little bit of powdery mildew and black spot during mid-summer heat, but they recovered on their own without being treated. There was a bit of Japanese beetle damage, but no treatment needed for that, either. I give them a little osmocote in the spring and mulch with leaf mold and coffee grounds.

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Posted by Newyorkrita (North Shore, Long Island, NY ) on Oct 16, 2011 10:54 AM

No spraying needed on Double Knock Out ever. Plus this rose really does like to bloom a lot. Not as much as the single version though, and if I had to do it over again, I might have gotten the single version Knock Out instead. The blooms on Double Knock Out simply do not fall when done and stay on the shrub in messy brown rotting balls unless I cut them after bloom. So I always do have to prune after blooming if I want it to look attractive.

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Posted by SongofJoy (Clarksville, TN - Zone 6b) on Nov 24, 2011 9:00 AM

Performs spectacularly here in my zone (6b). Although not fragrant, I planted it next to a fragrant rose to make up for that one shortcoming.

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Posted by Debbie (Denham Springs, La. zone 8b - Zone 8b) on Jan 2, 2012 5:38 PM

Absolutely wonderful plant. After trying about 50 other different types of roses, and growing discouraged because of the diseases associated with Southern grown roses, I finally found a Rose that needs almost no attention. They never have blackspot or rust and in Southern Louisiana humidity, that is a miracle. They should be spaced at least 4 ft apart. They bloom constantly from spring to fall. I was even able to have a vase of roses on my table in November. They actually look like a Hybrid Tea, which I love. What a joy to have blooms all the time . They should be transplanted only in early Spring while they are dormant. I enjoy walking slowly thru my garden and as I walk, I simply snip the older dried up blooms off. (I carry small snips in my pocket). In just a little while, the bushes are all full of blooms again. Love, love this plant!

How to Prune a Knock Out® Rose by ConardPyle
Follow these simple steps to prune your Knock Out®
Step 1: When do I prune my rose bush?
Prune your rose bush in early spring, never in the fall and never in the winter. Check your rose bush from time to time as spring moves along and when you start to see new shoots growing from the canes on your rose bush, that’s a good sign that it is time to prune.
Step 2: Use proper tools
You will need a few basic tools when the time comes to prune your roses: gloves, because of the thorns on your rose bush. Lopping sheers, for some of the heavier canes that are going to be difficult to cut with some of the smaller sheers. Small hand sheers, for some of the finer work, and a pair of hedge trimmers to get the job done quickly.
Step 3: Determine how high you want to prune
Determining how high you want to prune depends on how high you want your rose bush to finish. Your rose bush will usually triple in size after pruning so cutting it back to about a foot will leave it at 3 feet when it finishes growing.

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Discussion Threads about this plant
Thread Title Last Reply Replies
Rose cultivar ID question by Brazilnutty Apr 19, 2021 4:09 PM 4
Diseased Roses? by narnia Apr 18, 2021 5:19 PM 5
rose rosette disease or normal growth? by JGro Apr 7, 2021 9:17 PM 4
Petite knockout anyone? by teacup754 Feb 15, 2021 3:43 PM 12
Which roses have you ordered so far for next season (2021)? by zuzu Apr 17, 2021 5:43 PM 280
December 2020 -- Photos and Chat by zuzu Jan 1, 2021 3:56 PM 125
Red rose by kniphofia Sep 16, 2020 10:55 AM 6
Knockout Roses Dying by rjmctiernan Sep 15, 2020 6:44 PM 6
Hybrid Rose 'Chicago Peace' by RoseRidgeKim Sep 16, 2020 11:53 AM 33
All-America Rose Selections by Mike Sep 25, 2020 8:52 AM 25
Rose ID by Glaurious Jul 23, 2020 11:41 AM 6
Roses that can survive Mississippi? by CitrusSweete Jun 5, 2020 12:10 PM 6
New Container Rose Already Dying by Indigo8 May 27, 2020 4:44 PM 2
Looking for HT varieties for no-spray gardening. by MikeInBatonRouge Apr 1, 2021 3:57 PM 84
Rose variety help by centralcaligirl May 1, 2020 10:15 PM 23
Knock Out roses by Flowersgalore Apr 20, 2020 2:10 PM 8
Relocating Our Roses Advice???? by Weluvroses Jun 18, 2020 11:56 AM 180
Just something humorous with Knock Outs.... by cinvasko Sep 24, 2019 12:37 PM 16
Fed up with Sunny Knock Out by KenNEGA Aug 20, 2019 9:40 AM 4
Rosette Disease??? by Weluvroses Aug 21, 2019 11:09 AM 59

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