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Cottage Gardens

Prunning Knock out roses

16 years ago

I never pruned my KO roses because they stayed green and pretty all winter. Now they are quite large and starting to bloom. Can I prune them back now? If so how much could I cut them back by? I hate to lose the blooms but I think they are going to get too big for the area if I don't trim them.

faye

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Comments (7)

seamommy
16 years ago
Don't trim them while they are blooming. Even if they stay green in winter, that's still the best time to prune. Once the weather turns really hot, they may pause in blooming and you could do a little pruning then. But the best time is when the plant is dormant. Cheryl
PattiOH
16 years ago
Hi Faye,
I am a novice when it comes to roses, but I bought 6 knockouts, four years ago and have cut them back at various times for various reasons and they recovered.

Even though you will lose quite a bit of the current blooms by pruning now, my experience is that they will soon bloom again (or at least they do in zone5).

Also, since you didn't do any pruning in the spring, you may have quite a few of the little skinny "twigs" that could (and probably should) be cut down to the ground.

Roses of all kinds are often pruned in the summer to control their growth, so you could do it then too, as Cheryl suggested.

(Make sure they have enough room or you will be continually trying to prune them back. Most of the knockouts grow at least three feet wide)

Good luck!
Patti
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You probably didn't kill them, but you didn't do them any favors,either. Somehow, some folks in Tennessee have decided that roses are the same plants as other shrubs. This leads to some who severe prune as early as late September and again in November. This sort of thing takes strength away from the plants. Roses don't want to go dormant here. If you cut them in fall, they'll put out new growth in two to four weeks, even though it's not yet winter. That growth will probably be killed in late December, and that earlier cutting will have taken away the stored 'strength' that would go to regrow the plant in spring. I've watched some Knockout that have been pruned three times this fall. I don't know what the heck the grounds crew thinks they are doing, much less why. What you should have done (in my opinion) was go through and snip off broken canes. Then in late December go in and prune back for height, depending on how high you want them to be next year. The winter killed new growth that you are going to get, you'll see it contorted and blackened, you can snip it off in winter as well.
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fnboyd
Original Author
16 years ago
Thanks to both Patti and Cheryl. I am going to lightly trim them now and then again in the summer. I know now not to put this off.

faye
mehearty
16 years ago
Knockouts will probably bloom again 2 weeks after pruning, so go ahead and trim them up if you want.
lindakimy
16 years ago
I'm pretty new with these as well. Mine have gotten very, very thick - so much so that I'm a little worried about air circulation. Back when I grew hybrid teas I concentrated on that because it seemed to help with rust (black spot back East). I'm thinking about doing some judicious thinning but don't really know if it is a good idea.
PRO
Nell Jean
16 years ago
When I'm reluctant to prune any other way, I force myself to "prune" by taking bouquets.

One thing I've noticed about KO is that when a cane is cut back, say by a third, the new growth will be at a sharp right angle. In other words, I'll end up with a straight up cane with what looks like it took a sharp right turn in growth, kind of awkward looking.
Nell
louisianagal
16 years ago
That was going to be my suggestion, to just cut bouquets of roses or just the rosebuds. It is ok to prune KO roses really anytime. They are not meant to be pruned hard back like a hybrid tea in winter, but just to keep their shape and size. KO bloom pretty much all year, esp in the Deep South. Right now, mine in north MS are FULL OF BUDS and beginning to open. BEAUTIFUL! It is also fine to make thinning cuts which is to remove the entire cane to open up and aerate a rose. I usually remove canes that are going in a crazy direction or if things look too crowded. KO roses are pretty easy, thankfully.

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