The idea is a good one. The conversion (given you did convert this from an all colour photo to first a b&w to then make it a duotone - I think this is the word?) is good and I like the white background. Makes the transparent dry leaves even more so!
But I feel that you chose a bit too wide an aperture and too many of those delicate little leaves are out of focus.
Compositionally, I feel that I would not mind to see a little less white at the top and also on the right. But that is just me.