Armand - They are all straightforward photographs, except for the last "vines". It has some "character" that allows it to stand out from the rest in that it has grape at movement in it, it is a more dramatic composition and it is B&W.
I'm not sure how to say this, but we are in the User Critique section... As these are "portraits" of the subjects you've chosen, you might find even more success if you really work at portraying them in their best light, in a way that exhibits their unique character. For example, lumpiness have such a dynamic flower structure, colour and leaf shape. You want to accentuate those aspects. Soft backlighting works; combine that with a background darker than the flowers and that would elevate both shape and colour.
The trick is to stop and ask yourself, what am I trying to do here? Why am I photographing this? What caused me to stop and consider setting up? What am I trying to say? Once you can articulate answers to these questions, use your knowledge of photography to accentuate those characteristics? If done well, the answer should become apparent to objective viewers once they begin to study your work in detail.
Also, grabbing viewers' attention with a unique view or composition is a good way to guide your composition. I always consider what I've seen before and try to make something different of the scene. While one can become obsessed with the dramatic, I find it easier to scale back on drama to fit the scene/subject than to try to add drama artificially when it is lacking. You haven't done this - and that's a good thing. But, like a good novel or newspaper article, look for ways to hook your viewers. Backlighting is a good place to start.
