First: Very nice photo and a nice placing among so many entries.
First impression: Like the cropping and placement in the frame. ONe of those subjects that begs for an up front and center placement.
Composition and color: as stated above, I think you did a good job with this photo. As one comentator mentioned below, the purple could have been saturated just a touch more. The positioning of the plant, rotation wise, looks good, it gives a 3D effect in its current orientation.
Lighting: My favorite part of this photo is the way the light falls off as it travels down the stem/stalk. The greens are also very nice with a good clean focus throughout.
Challenge: The voters have spoken. Good job and a fine subject for the challenge. Keep on shooting!
This picture is awesome! It could use just a touch more contrast or saturation though, I think. The purple seems a bit washed out compared to the absolute black of the background.
I've realized from my own entry that this is a difficult shot. It's hard to make leaves with light shining through them sharp because you have all that thickness to work with. Good job. 8