I don't believe I have seen this particular flower before, but I definitely like the shape of it. It reminds me of my Bleeding Hearts in some way... tiny and fragile...
I particularly like flower macro shots these days, as I have been trying to do some myself. Composition is important as always and sometimes the exposure can be a challenge in itself, especially with white flowers.
The composition you chose here works very effectively... the diagonal of the stem leads nicely to the small and shapely blooms on this flower. The shallow depth of field also nicely separates your subject from the environment.
The tonal/color range in this photo seems to be just a little flat. I don't know how to really fix something like that when dealing with white flowers without losing the detail on the flower. Those subtle textures are important and over exposure will wash them out very quickly.
This image also seems to be just a tiny bit soft. It could be from a slightly soft focus, but not entirely sure.
Neat. A unique type of flower. The lighting on this one is good, and the composition fairly tight. The stem is emerging a little close to the corner, which feels awkward. Nice DOF.
Great DOF and compostion. I would love to have seen this flooded in sunlight to highlight those flowers more. But I guess you can't control the sun right? Well done.
This is excelent. But I wonder about the focus. Seems a tad soft to me. If I remember correctly though, this kind of flower has a funny texture, which may be just making it seem like it's soft focus. Sometimes textures really mess with a photo. The angle and framing/cropping are nice. The color is good as well. You have done a nice job blurring the background as to not make anything distracting. Good luck in the challenge.