Was actually shooting this for the delicate challenge but when I over exposed and got something similar to this I went ahead and shot more to see what I could submit here.
Slight color adjustment to correct white balance (dang thing wouldn't work right on the camera).
Brightness adjust
crop
Levels
curves
USM
Convert to 8 bit
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Place: 190 out of 277 Avg (all users): 4.5978 Avg (commenters): 4.6250 Avg (participants): 4.3269 Avg (non-participants): 4.7616 Views since voting: 927 Views during voting: 346 Votes: 276 Comments: 9 Favorites: 0
'Orchid' is your entry into the 'Light On White II' challenge. As you mention in your comments, you were actually shooting this for the Delicate challenge and I think it fits that challenge better, however:
Technical:
You have used maximum size and this helps a lot in a challenge. The crop is not too tight and the image has not been overly sharpened which would have made it really overpowering. The background could be anything, there is no hint of any texture, but then the challenge did ask for a white background. Focussing and DOF are good with the centre of the orchid being the focal point.
Composition:
Subject leads in from bottom right corner to a central format image using portrait setup. The cropping works well, there is a satisfying white border on the sides. With no shadows, there is an unnerving starkness about this image, possibly because the colours of the flower are so striking.
Overall:
I like the shot, but I don't think it quite fits the challenge and hence the lower than normal score. There is nothing terribly wrong, nothing that deserves harsher critique. I think you are well aware that you have misjudged the challenge and therefore faced a lower score when entered in a different challenge, would have attained a much higher score. I hope this is helpful and constructive.
It needs something in the background. Think of the famous Ansel Adams picture of a rose on a piece of wood. The primary focus is still the flower, but there is something other than blank space in the background.