Why does my Knock Out Rose have bright red new leaves? - Ask Extension
This is an old Knock Out rose. It's new leaves are bright red. Is this normal? I've heard these roses are being attacked by a virus. Should I worry? T...
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Why does my Knock Out Rose have bright red new leaves? #548585
Asked March 24, 2019, 9:19 AM EDT
This is an old Knock Out rose. It's new leaves are bright red. Is this normal? I've heard these roses are being attacked by a virus. Should I worry? Thanks for your help.
Prince George's County Maryland
Expert Response
Please send us photos so we can see what you may be dealing with.
New growth on roses can be red. Also, there is a virus called rose rosette. The initial symptoms are reddening of the stems and stunted growth. Take a look at our website for photos. http://extension.umd.edu/hgic/topics/rose-rosette-shrub
mh
New growth on roses can be red. Also, there is a virus called rose rosette. The initial symptoms are reddening of the stems and stunted growth. Take a look at our website for photos. http://extension.umd.edu/hgic/topics/rose-rosette-shrub
mh
New leaves coming in are very small and bright red with touches of green. Read article. Early in season so hard to tell. Looked at stems. A little red.
Sending pictures. Hard to send for some reason. Trying again.
Hope can send this time. Probably doing something wrong. Oh Well.
We received your photos, thank you.
That does not look like Rose Rosette Disease, which is good news! New growth on many roses is red like that.
There are signs of lesser, but common canker diseases on the stems (the blackened areas) which can slow the rose down. You can prune those back as much as you want- even to the ground, but it will sacrifice some flowers and take a while to recover.
Generally they do like to be pruned back to solid branches just above an outward facing leafbud.
Pull the mulch back from contact with the base of the plant, and don't mulch deeper than say 3-4 inches.
cm
That does not look like Rose Rosette Disease, which is good news! New growth on many roses is red like that.
There are signs of lesser, but common canker diseases on the stems (the blackened areas) which can slow the rose down. You can prune those back as much as you want- even to the ground, but it will sacrifice some flowers and take a while to recover.
Generally they do like to be pruned back to solid branches just above an outward facing leafbud.
Pull the mulch back from contact with the base of the plant, and don't mulch deeper than say 3-4 inches.
cm
