rose bush - half healthy and half very unhealthy - Ask Extension
I've had the attached rose bush for 10+ years and it has thrived until this year. Half of the bush looks great. The other half has spotted leaves, t...
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rose bush - half healthy and half very unhealthy #807361
Asked August 21, 2022, 7:33 PM EDT
I've had the attached rose bush for 10+ years and it has thrived until this year. Half of the bush looks great. The other half has spotted leaves, the stems have spots and are blackened and the leaves are falling off like crazy. And then there is a small section of the same bush that has tiny little leaves growing (this section is in between the "healthy" and "unhealthy" section). I was wondering if you have any suggestions on what is going on and what I should do to treat it. I named the picture files named for the various parts of the same bush.
Clermont County Ohio
Expert Response
This shrub looks like a Knockout rose which are very disease resistant. I have no explanation why half has disease and the other half does not. But, rose diseases are treatable. Without a photo of the effected leaves, I am guessing that they had black spot. Very common and does not cause the death of the plant.
I am not sure why the leaves are small, I can't really tell much from the photo. My suggestion is to clean up the rose bush as much as possible. Rake up the debris from underneath and dispose of it in the trash. Then apply a fungicide listed for rose diseases according to the label. The rose bush should leaf back out on the bad side before the end of summer.
Rose Black Spot (psu.edu)
I am not sure why the leaves are small, I can't really tell much from the photo. My suggestion is to clean up the rose bush as much as possible. Rake up the debris from underneath and dispose of it in the trash. Then apply a fungicide listed for rose diseases according to the label. The rose bush should leaf back out on the bad side before the end of summer.
Rose Black Spot (psu.edu)
