Here's a couple repetitions in the color purple that I happened to notice recently. In neither case do the purples exactly match, but that doesn't seem to matter for their impact, which I have to admit is better in person. Perhaps this has to do with the color punch being small in the field of view when there in person versus dominant in the field of view in the photos.
The first photo is from RSABG. You'll have to imagine the salvia when it's larger, but to my eyes there's a clear visual link between the butterfly garden ornament and the flowers that enhances both
In the photos below, the color differences between the purples seem to be enhanced, but perhaps this is due to the close visual juxtaposition of the chair with the flowers: I positioned the chair to capture the flowers in the same photo more easily. In actual practice, the chair sits farther from the flowers and the splash of color continuity works really well as one looks about the garden, but you have to shift your gaze from most vantage points to notice it. A bright lime colored chair of the same design has less visual impact, presumably because there's less continuity with the same color family in the garden.