Hi Michael. I love the subject matter here. We don't get to see many thistles where I live. I need to drive about 60 miles to get to a place that's wet enough to have them growing in the wild.
I suspect that the thistle is the main subject and as such, it would be good if you could zoom in on the flower and try to remove as much of the background as possible. Right now it competes too much with the subject. A wise teacher I once had told me "If it doesn't add any esthetic value to the image, get rid of it".
Agree with Michael here, i like the subject, infact it reminds me of being in Scotland. as its their national flower. the focal point the flower needs better framing, but the colours & lighting are very nice. an off centre alignment of the subject could be nice :~)