Your camera settings worked well to capture this dahlia in high key. The image is very clean and provides and reminds me of a detailed colored pencil sketch of this flower. I would be tempted to crop some off the bottom of the frame. Very well done…Jim
f/36 did the trick. Good sharpness and detail. You could try nudging the blacks a bit deeper here, it seems a tad light to me and I agree with Jim about losing some at the bottom. If you use the TK panels you could experiment with masking the middle of the flower and deepening the blacks just there. Great color. I can imagine how beautiful they are in your yard.
Thanks for the comments @Kris_Smith. I subtly increased the blacks in the flower center using a radial filter in Lightroom. I just acquired the TK panel and am still learning how to use it. I also used @Jim_Zablotny’s suggestion and cropped a little off the bottom.