landm42006
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Knockout roses getting knocked out!

Hello all, and sorry for the lame subject topic. I have 4 year old knockout roses that are on the South side of the house and they love it there. Lots of sun and I always give the right amount of water. The only trouble I have ever had with them is the stupid Japanese Beetles in the summer, and as you all know, this summer was bad since we had hardly any winter last year. Well, my problem this year is my next door neighbor saw me deadheading my rose bushes by hand and told me that he uses his hedge clippers and it works great. His rose bushes are full of leaves and flowers, and the funny thing is, is that they're clippings from my bushes. Well, I took his advise and did just that. Well, it's been 2 months now and my roses look HORRIBLE!!!! All of the foliage is falling off and it looks like some of the canes are dying, but when I scratch the cane, there's still green underneath so that gives me hope. My question is, did my using the hedge clippers kill my bushes or could it be something else?? I have looked all over to see if it's a bug or disease killing it, but I can't see anything. My neighbors bushes look great so that makes me believe that it's not from the clippers. Is anyone else having a problem this year? I will take a picture tomorrow and post it so you all can see. Thank you for any input you can give me. God bless.

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rainbowgardener
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I'm not a rose grower and the picture will certainly help for those who are.

But one thing that occurs to me is that it could depend on what you did with the hedge clippers. Hedge clippers are meant to just shear the outside edge off the hedge, all the little branches sticking out, to give it that smooth finish. Your neighbor probably uses it to take off the dead flowers all at once instead of one at a time, without taking much stem.

If you used your hedge clippers like pruners, cutting IN to the shrub, you would get a lot different results than if you just used them going over the outside.

Otherwise, I wouldn't think it would be the clipping. If it is from the Japanese beetles, the foliage wouldn't just fall off, it would have tons of holes in it, perhaps to the point of being skeletonized, if it's a severe case.

One thing that helps for the JB's is to grow some grape vine (even wild grape vine, the weedy kind) nearby. It's something they love even more and it is a great trap crop for them.

landm42006
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Thank you for your response. I took some pictures of my sad roses and I also took one of my neighbor's who's are clippings from both of mine and he is the one who uses the hedge trimmers. I looked all over for bug damages and luckily, there are none, so that's what makes be think that this is damage from my harsh pruning. So my next question is, what should I do to help my roses along?? Miracle Grow, any type of mild fertilizer or just TLC and time?? I appreciate ANY advise from you all. Thank you again. God bless.

landm42006
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Sorry, I couldn't figure out how to upload pics. I hope someone can tell me what to so. Thank you all. [img[img]https://i1248.photobucket.com/albums/hh483/lmartin9192000/495e4793.jpg[/IMG[IMG]https://i1248.photobucket.com/albums/hh483/lmartin9192000/2e1e79c8.jpg[/IMG[IMG]https://i1248.photobucket.com/albums/hh483/lmartin9192000/58bb3a6c.jpg[/IMG[IMG]https://i1248.photobucket.com/albums/hh483/lmartin9192000/e17b9663.jpg[/img][/img]

landm42006
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[img[url=https://s1248.photobucket.com/albums/hh483/lmartin9192000/?action=view&current=495e4793.jpg][img]https://i1248.photobucket.com/albums/hh483/lmartin9192000/th_495e4793.jpg[/img][/url]
[url=https://s1248.photobucket.com/albums/hh483/lmartin9192000/?action=view&current=58bb3a6c.jpg][img]https://i1248.photobucket.com/albums/hh483/lmartin9192000/th_58bb3a6c.jpg[/img][/url]
[url=https://s1248.photobucket.com/albums/hh483/lmartin9192000/?action=view&current=2e1e79c8.jpg][img]https://i1248.photobucket.com/albums/hh483/lmartin9192000/th_2e1e79c8.jpg[/img][/url]
[url=https://s1248.photobucket.com/albums/hh483/lmartin9192000/?action=view&current=e17b9663.jpg][img]https://i1248.photobucket.com/albums/hh483/lmartin9192000/th_e17b9663.jpg[/img][/url][/img]

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rainbowgardener
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[img]https://i1248.photobucket.com/albums/hh483/lmartin9192000/495e4793.jpg[/img]

[img]https://i1248.photobucket.com/albums/hh483/lmartin9192000/58bb3a6c.jpg[/img]

photobucket makes it very easy. Just click on the IMG code they give you, which automatically copies it. Paste it in here. You don't need to use our Img button or anything. Pictures come through better that way and enlarge when you click on them.

Hopefully now, some rose grower will have better answers for you. I agree they are certainly looking sad. This time you said "my harsh pruning." Does that mean you did more than shear the outside of yours? I would NOT fertilize at this point. When plants are suffering, adding synthetic fertilizer is just another stress.

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applestar
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I agree. I'm not a rose grower either, but generally speaking, you don't want to fertilize shrubs and trees with high N/fertilizer that stimulates new growth when fall approaches because any new tender growth will most likey be winter-killed.

Again, not rose expert, but the browned leaves reminds me of fireblight in apples and pears. I wonder if it's possible that the trimmer had been used to prune infected pyracantha, etc. other rose/apple family and infected your rose? OR the hedge trimmer did not leave clean cuts that caused infection to set in since it has been rainy and humid along the Atlantic coast?

I would use a sharp pair of pruners or loppers to make a clean cut below the browned branch (cut off the browned branch) and see if the cut end shows brown under the bark layer instead of all creamy white.

If it does, disinfect the edges -- I use rubbing alcohol in a personal atomizer you can buy at drug stores but I think the usual recommendation is to dip in chlorine solution -- and cut few inches further down to healthy uninfected branch. Spray the cut on the shrub (or paint with whatever you normally use after pruning).

Bag and discard the infected branches in trash or burn them.

Oh, one other possibility that just now occurred to me. Is your hedge trimmer gas fueled? Is it possible some oil got on the foliage and burned them? I guess in this case, if the branches are not browned/shriveled/dead, they may recover and grow again so you may not want to make as drastic initial cut at first.

cynthia_h
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Speaking from general rose experience, not from knockout rose experience, and my rose care is pretty lackadaisical, but ...

Let me suggest a sequence, almost a flow chart. This may NOT be what has happened, and is completely DIFFERENT from what the previous respondents have suggested.

1) You were dead-heading the roses "way back when," when your neighbor suggested the hedge trimmers. Had you pruned them last fall or in the spring?

2a) If you did prune them last fall or in the spring, I believe the center turned brown due to excessive heat and lack of water. The outer leaves can glean some moisture from overnight condensation, even the small amounts available in most parts of the country this summer, but the inner branches? No. (Note: I don't know *where* in North Carolina you live; maybe you've had rain.)

2b) If you did not prune the roses within the last year and they were somewhat overgrown when you went at them with the hedge clippers, there's a possibility that the center not only was dried out, but that it has *also* suffered from sunburn (called "sun scald" when it happens to plants, but we all understand what it means) because of the sudden exposure to full-on sun in midsummer in the South. Ouch. That, plus the many temperature records set this year in our country and no water...well...see 2a).

3) Insects can be vectors for disease. I don't know which disease(s) the Japanese Beetles specifically can transmit, but they cannot have been good for the plant. They may have weakened it so that, when the hedge clipper episode took place, the "browning out" followed.

My recommendations--I always err on the conservative side, leaving room to take more drastic action later, if necessary. It's difficult to replace foliage or branches that have been removed later, but always possible to take them off at a later time.

1) Use a hand fork to lightly scratch in some compost near the roots of the rose bushes. It's fine if most of the compost remains on the surface; watering will move some of it down, and earthworms will also bring a lot of it down to the root zone.

2a) Then, unless you're on water restriction, give the roses a DEEP watering. Use a trowel to dig a 3- or 4-inch deep moat around each bush at its dripline, approx. 2 to 3 inches wide. (This will also move some of the compost beneath the surface.) Fill this moat with water. Let the water drain to the roots of the bush. Fill it again. Let it drain again. Repeat in a week. Do this as long as there is no decent rain ("decent rain" = > 0.5" in one event).

2b) If you *are* on water restriction, take a 3-gallon bucket or convenient sized pail into the house. When you're waiting for the shower to warm up, let that water run into the bucket. Later (e.g., after the shower!), pour the water into the moat. If you have a laundry sink that your washer drains into rather than hidden plumbing, use the last rinse water for the roses. Again, catch the rinse water in the bucket (you may need to stop the washer a few times to catch all the rinse water) and transfer it to the roses. A top-loading washer should take care of the roses nicely with just one or two loads (I have a top-loading washer and yes, I have transferred rinse water to my plants previously).

Best wishes.

Cynthia H.
Sunset Zone 17, USDA Zone 9

landm42006
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Joined: Sun Jul 08, 2012 12:52 pm
Location: Salisbury, NC

Thank you all for your help. I normally prune my bushes in early spring if they need it, sometimes I skip a season if they look good. I wish I would have NEVER listened to my neighbor, because reading all of your responses, using those trimmers may have ruined my 4 year old rose bushes. I've done everything that you all have advised and his trimmers were very dull and he also had just used them on holly bushes and weeds. I'm STUPID!! I know better than that. I am a very meticulous gardener and keep my tools very clean and now my moment of frustration with deadheading may have cost me my lovely Knockout roses. :( I have gone through and clipped all of the chopped up branches, gave them a god drink of water and compost and with some tlc and time, hopefully they will bounce back. Thank you again for all of your quick and very helpful advise and hopefully my next pictures will be of my beautiful bushes. Thanks again and God bless.



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