Help with Knock Out Roses

daisyntnNovember 8, 2005

I am new to the Maryville area and a newby to gardening. I need help on how to care for knock out roses. I would appreciate some guidance. Thank you so much.....


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reneecd(z7 TN)

Is there something specific troubling you about the knockout roses? As long as you plant them in well draining soil, they pretty much take care of themselves. I fertilize once in spring and once in late summer and I rarely supplement the rain water unless we get a drought in the heat of summer. It is not necessary to deadhead, unless you just want to tidy them up for a garden party :) I prune mine just to maintain a rounded shape and keep them in bounds.

Let us know if you have specific questions.

    Bookmark   November 9, 2005 at 11:03AM
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anntn6b(z6b TN)

Or don't prune them and let them grow taller (and covered with even more blooms.)
They don't need to be protected in winter in our part of TN, nor do they need much help. If they are new, they might like some supplementary water through this drought as they won't go dormant until January, if then.

    Bookmark   November 9, 2005 at 11:41AM
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I love my Knock Out Roses! They seem to need so little care. Mine don't like water sprayed all over them, but they do like water by their roots. I had some mites or thrips this summer, so sprayed a little diluted malathion on them and they disappeared. I deadhead mine, but only the end bracket. Mine are blooming right now and are about five and a half feet tall on sturdy canes. The one mistake I made was to plant them in the middle of my bed. They should be in the back as they grow taller than anything else around there. I will transplant them later this month. I know they will come back because these babies are ROBUST! I love Knock Out roses!--caroleann

    Bookmark   November 9, 2005 at 6:09PM
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I love my Knock Out Roses! I have both the original "Knock Out" and "Blushing Knockout" which is a soft pastel pink. There's a new one out now, "Pink Knock Out" which has brighter pink blooms. I'm going to have to get one of those next year.

I have a "Carefree Wonder" that I'd hoped would live up to its name, but it doesn't. They should have reserved that name for these Knock Outs. I've seen no sign of blackspot or powdery mildew and have had no insect problems, so have not had to spray them a single time. You don't even need to deadhead these roses since the petals fall off cleanly, but doing so should increase the number of flowers since the plant won't be putting energy into producing seeds. It's your call.

Here is a link that might be useful: Knock Out Roses

    Bookmark   November 10, 2005 at 1:02PM
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sondra_tn(South East TN (6/7))

WOW...I love those...big rose lover here....May have to get some of those. I have 18 rose plant's and several I don't know what they are...LOL
Daisy, You are not too far from me either...I am up in the MTNS past Tellico Plains....:))

    Bookmark   November 11, 2005 at 9:02AM
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you seem to know much about these roses.i will ask.can you buy them in 3 gallon containers and what might that cost? can they get taller than 3 feet?would it be a bad idea to plant them down a driveway? ty.

    Bookmark   November 13, 2005 at 11:50PM
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reneecd(z7 TN)

Yes, you can purchase them in 3 gallon containers. At the local nursery I checked, they were $30 for this size. The original knockout will get 4 or 5 feet tall and wide when mature. The Blushing Pink variety stays much smaller in my experience. I don't know about the new Pink Knockout color.
They would be beautiful planted along your driveway as long as you have room for a wide bed.

    Bookmark   November 14, 2005 at 1:08PM
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Soeur(z6b TN)

There's also a new Double Red Knockout, with loosely doubled blooms. I saw it at the big SNA do in Atlanta this summer. Very very pretty.


    Bookmark   November 14, 2005 at 7:21PM
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reneecd(z7 TN)

Oh yea, they had those for sale at Bates this summer. Same look as Flower Carpet roses but so much better foliage & disease resistance. I hope they will be more affordable next season.

    Bookmark   November 15, 2005 at 10:24AM
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anntn6b(z6b TN)

They are already more affordable, if you'll accept a smaller plant (that will catch up by next spring.)
Appalachian Rose just northeast of Tellico Plains has three of the different colors of Knockout at very good prices, as well as other well grown roses at prices better than the fancier stores.
The owner is a friend of mine and I buy from him whenever I can.

Here is a link that might be useful: Appalachian Rose

    Bookmark   November 15, 2005 at 12:21PM
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I recently planted two Double Knockout Roses. One of them has produced numerous new growth shoots. The other has only one small new shoot. It also has some dark spots on some of the leaves. Do I need to fertilize/feed these roses? Also, the one that is growing has aphids on the buds. Do I need to spray? I am very much a novice gardener and would appreciate any information you can share. Thanks!

    Bookmark   May 17, 2007 at 9:02AM
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Spraying the aphids with water should knock them off. I'll also pass on an aphid trick that a gardener passed on to me last week. You can try it and see if it works for you. She sprinkles flour on the aphids, leaves it on for about an hour and then rinses it off. Supposedly the flour smothers the aphids.
The other thing to keep in mind is that a few aphids shouldn't hurt a Knock Out rose very much. Good luck.

    Bookmark   May 20, 2007 at 11:56PM
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Hello. I have a double knock out rose that is blooming in only approximately a fourth of its area. The rest of the rose bush is nice and green and looks healthy but it is not blooming. Any ideas?

    Bookmark   June 9, 2007 at 9:30PM
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anntn6b(z6b TN)

Check the soil for burrows (as in made by moles, but recolonized by voles that love the taste of Knockout roots.
Or it could be damage from the Easter Freeze that took out the buds on the warmer side of the rose that were just a bit more mature (and vulnerable to the three nights of serious cold - for that time of the year.)

    Bookmark   June 9, 2007 at 11:23PM
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I am a new gardener and about a month ago I planted 3 knockout roses. They bloomed very well untill recently. They look healthy but there is only a few blooms between the 3 of them. I tried fertilizing them, but no change. What could be the problem?

    Bookmark   June 16, 2007 at 3:53PM
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I'm new with gardening and have 1 yr old Knock Out Roses. I have noticed a problem that is getting worse. The leaves seem to be getting eaten up. The leaves have all these holes on them. Can you tell me what is causing this? What do I need to do to treat this problem? I prefer as little chemicals as possible.

    Bookmark   June 16, 2009 at 9:02AM
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Mimmikay, I have 20 knockouts that I planted last year around my porch. They are beautiful and about 4 ft. tall. My brother liked mine so much he planted them along his retaining wall. His had the same problem as yours and I was starting to have trouble too. We found that the damage was probably caused by sawflies. We both sprayed with liquid sevin and It solved the problem. I try not to use pesticides too, but the knockouts are so gorgeous that you at times have to do something. The damaged leaves are coming back. Good luck....I also want to add that we tryed Bayer rose spray and it did not help.

    Bookmark   June 16, 2009 at 12:17PM
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judydean(z7b TN)

I have discovered that Lowe's puts things that aren't blooming anymore on clearance and I picked up a KnockOut Rose called "Rainbow Knock Out Rose' which was a pale pink with a yellow center. It was originally $19.98 but was marked down to $7.50. All it needed was repotting and water and it's doing great! If you aren't in a hurry, you can really get good bargains at the end of the season. I love mine!!

    Bookmark   June 20, 2009 at 8:08PM
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I need help with 37 Knockout roses. Some are doing real good, some have leaves turning a pale yellow, some have little bumps on stems that give me hope. Some are just barely living. I had ants--got rid of those. Watering and fertilizing with Rose food twice a week. They get at least 6 hours sunlight a day even tho they are under two very, very old oak trees. I do not know what else to do. Would appreciate any help out there. Thanks.

    Bookmark   July 11, 2009 at 10:10PM
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I'm certainly no rosarian, but I can tell you what I know about knockouts:

I have read that you don't need to fertilize knockouts, especially in their first year.

I have about 17 planted against our fence. Some are doing better than others. I have planted them before and they struggled their first year, but really took off the second year. Once they are established, you're gold.

I bought several whites and planted them this spring. I was really complaining about them and almost to the point of pulling them up, they were so embarrassing. I left them in and lo and behold, they are drop-dead gorgeous now. Blooms all over each of them, and putting on new growth.

I did nothing to them except water. I also think they seem to enjoy being deadheaded (picking off spent flowers). This has seemed to encourage a flush of blooms every time I've done it.

The red knockout I had at the other house did not bloom non-stop. It took a break in the hottest part of the summer, and started back up again when it got cooler. Or maybe it has to do with water. I didn't give it supplemental water (let Mother Nature water it for me), but if I had maybe it would have bloomed more continuously.

I say don't give up on them. They may surprise you. My white ones have sure surprised me!

    Bookmark   July 12, 2009 at 8:08AM
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I have 2 knockout roses that are blooming great, but the leaves are full of holes. It could be Japanese beetles but not sure, can't find anything on them. What should I use on them to kill whatever is eating them. Thought they there bug resistant. Also I dead head them all the time so they look much better. Is that necessary? thought that wasn't needed. Thanks.

    Bookmark   June 17, 2010 at 3:03PM
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I def agree with Judy; Lowe's is GREAT if you need a lot of plants.... or just one. LOL I never pay full price for plants, they always have a clearance rack for stuff that not blooming.... last week I picked up 2 Hydrangeas and 2 reblooming Azaleas for $5 each..... yesterday I scooped up 3 knock-out rose bushes for $5 each, 18 (yes, 18!!!) white lilies, 6 red lilies, and 12 "Pinacolada" Red Beard Tongues for ............ drum roll...... $1.00 each!!! :) (No, I *don't* have the slightest idea where to put them, but they were only $1.00!!!!!) LOL

    Bookmark   June 26, 2010 at 3:48PM
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No rose expert, in fact my motto has always been if I can eat it I'll plant it; wifey takes care of the pretty stuff. But her health has led me to getting involved. We have over a dozen Knockouts. Since I'm a cheapy, I purchase the little ones, never pay more than $5, watch them struggle a little the first year and take off like a race car the second. Whenever they get spots on their leaves or see something crawling around, don't do too much analyzing, just spray them with liquid seven, get the jug type where all you do is hook up your hose and the next day all is well. It only takes a squirt or two. Still using my original jug. When I only had a couple of knockouts would do some deadheading and yes they do bloom better but got too many now. Oh yes, a little rose fertilizer 2-3 times a year must help because thatÂs what I do and they look great.

    Bookmark   July 3, 2010 at 7:38AM
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I put my knock out roses in the wrong place, I did not know it would get so big. My question is can I move it. I have had it for 2 years. I live in Memphis, Tn.

    Bookmark   April 18, 2011 at 10:06PM
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brandon7 TN_zone(7)


Of course you can move it! Better do it soon though. The heat of summer is just around the corner, and your rose needs to start getting established before that time for best results (and less work on your part to keep it alive).

    Bookmark   April 18, 2011 at 10:45PM
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Folks, just Google knockout rose and you will all be experts in 30 minutes. You sure save a lot of money if you purchase quart size. They may not be great year 1, but year 2 they will be fine. As for aphids and discolored leave, I always keep a spray quart of Sevin around. It can be found in Walmart or Lowes, & is cheap, has many good uses.

    Bookmark   April 19, 2011 at 6:05PM
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Before Knock Out roses my best advice for growing roses would have been "try to kill one and it will thrive... baby it... and it will surely die!" However, this spring my hubby and I purchased three "Sunny" (yellow) Knock Out roses... for first attempt at growing/enjoying them. We found them at Lowe's for $15 each. I think they were in gal size containers.

I have high hopes for these plants! I'm expecting great things!

Thanks for all the words of wisdom y'all have provided!

    Bookmark   April 19, 2011 at 9:43PM
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I live in Fort Worth, Texas and this is the first time planting double knockout roses. I bought them 2 weeks ago and planted them in my yard. They were full of roses. One week later, all the roses are drooping and shriveling. What did I do wrong??? I have been watering. Do I have to remove these dead appearing roses? Some say, not to deadhead, but how will new roses grow? Can someone please advise. I planted 7 large plants and would hate to lose them.

    Bookmark   April 20, 2011 at 1:55PM
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Two of my knockout roses have yellowing and dried up
leaves. I sprayed with a fungicide, but haven't seen
results. Should I cut off the dried up leaves? I have
fertilized the roses and water them frequently.

Thank you.

    Bookmark   June 3, 2011 at 2:24PM
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katiedidcottage(z7 TN / Chattanooga)

I had 1 beautiful large knockout rose I planted 2 years ago. The first two years, it would flourish for a while and then drop all the leaves and what was left would look yellow and look absolutely dead for a while only to come back and flourish again. I'm pretty good with plants but could see no rhyme or reason for this behavior. This year, so far it has flourished and not died back. I also planted 2 yellow knockout roses that had been marked down half price and they seem to be flourishing as well. I'm thinking maybe they need more water than I initially thought, so I am trying to keep them watered at least twice a week.

    Bookmark   June 5, 2011 at 1:13PM
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Help! Second year for my double knockout roses, started out well now blooms are brown on the edges before they open up, I deadheaded them as they were unsightly now no sign of any blooms on one plant, I water twice weekly as they are in wooden barrel containers.

    Bookmark   June 7, 2011 at 7:11PM
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HELP! I received a knock out rose plant as a gift and absolutely love roses so I was thrilled with the gift. Unfortunately, I am the last person you should give plants to as I can't even get a cactus to grow! Anyway, have had the plant just over a month. I keep the soil moist with plenty of sun but the leaves have all turned brown and dried up. The stem is still green. Too much water? Too little? Not enough sun? Too much sun? I don't know how to "revive" my plant but sure would like to keep it around. I will appreciate any advice...

    Bookmark   July 5, 2011 at 3:14PM
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I thought I was supposed to prune my knockouts down before winter freeze..Oops.. Any chance they'll come back in the spring? What can I do in the Spring to encourage growth or do I have to get new plants?

    Bookmark   February 19, 2012 at 2:54PM
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anntn6b(z6b TN)

As long as your plant developed a good root system last year, it will come back this spring. Come late March, give it some all purpose fertilizer.

    Bookmark   February 28, 2012 at 11:39AM
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bought 2, from diff places. both had blooms on them. they both continued with blooms for about a week. then nothing. all blooms fell off and not a sign of one yet. no buds. foliage is great though. what is wrong? any ideas? too much water, not enough. they get sun. help!

    Bookmark   June 15, 2013 at 9:56PM
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My Radsunnys are in their 2nd growing season. These are THE WORST. I am debating whether to yank them out - I'm no rose newbie- just don't get why they are such poor performers. Is there hope ?

    Bookmark   September 15, 2013 at 5:53PM
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I have close to twenty five Knock Out roses. I also was infested with saw flies this year. My Knock Outs always bloom three times spring, summer and fall. After the summer blooms is when the holes started appearing and within a couple days the leaves were riddled. I decided to use the dish soap in a hose in sprayer. I sprayed every plant I had on the place hostas, roses, evergreen type shrubs, every plant in my gardens. I fixed those bugs but I also stopped my roses from blooming for the rest of the season. The buds would start to appear, dry up, turn black and fall off. Am I sorry, No, as all my rose plants became bug free and the rose leaves were a lush beautiful blue green almost prettier than the blossoms would have been. Hum, Now I'm thinking I am on to something and I am going to spray that nasty huge blooming tree over my patio, which drops something or other, say nothing about the birds taking aim, all summer long with the same treatment before it blooms so it will not have those blossoms, stems and little red apples falling all over my furniture. It is one messy tree and in the early winter the starlings move in and clean up all the berries in a matter of hours. Of course they leave their calling card. Call me devious but I am bug free. After thought, I guess I will forget the spray on my lovely shade tree and let the birds enjoy their feast. What's a little red berry stain on the carpet in my home.

    Bookmark   September 21, 2014 at 8:25PM
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Update: a year later- Radsunnys still under performing- I didn't yank them out- bought a few more & planted right next to the old ones so they would look more filled out. Bought the double pink- it's been in the ground a week and looks better than the 3 yr old yellow Radsunnys. I have to fertilize them bimonthly to get any sort of bloom out of them. My reds are always blooming- Never fertilize or water. Occasionally - I deadhead them all. Just the yellow knockouts totally suck.

    Bookmark   September 22, 2014 at 1:04AM
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Am trying to understand why I wanted yellow roses in the 1st place ... Hmmm I need to move the Radsunnys to a shadier spot perhaps. Have them on the west side of the house- I have other roses that don't mind the exposure & perform very well. A climbing Peace rose, Cecile Brunner, Don Juan climber & Tropicana hybrid tea. They do outstandingly well. Makes no sense. Except Radsunnys are losers ? Don't know !

    Bookmark   September 22, 2014 at 1:11AM
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