Knock Out rose has become a ubiquitous part of urban landscapes in the last decade. It blooms reliably and is resistant to black spot leaf disease.
Usually it is trouble free.
However, I have noticed several instances where the rose just “up and dies” for no apparent reason. I don’t know why this happens but I’m curious if it could be an infestation with chilli thrips.
This insect is well-known in Florida, where it is a recognized threat to Knock Out roses. The creature is not supposed to live this far north….but maybe it isn’t behaving as expected.
If you have a declining Knock Out rose and want to do more investigation, read this
Chilli Thrips Threaten Roses
then see these images Chilli Thrips
Check your roses for thrips as noted and let me know if you find them.