Green flowers were all the rage a few years ago. I don't know if they still are, but as usual I lag the trends when I'm not way ahead of leading them...
Arisaema amurense, one of the oriental relatives of our native Jack-in-the-Pulpit; the oriental ones usually go by the common name of Cobra Lilies. Clean, simple lines. (and apparently unable to decide how many leaflets make up a leaf)
Better known, the Stinking Hellebore Helleborus foetidus. Well, it doesn't stink noticeably to me, but maybe a field full of them would? The first photo is of a new flower which has not yet been pollinated.
The second is of a couple of older flowers which were pollinated a while back; note the ovaries in the middle and the absence of pollen and anthers, which have fallen off.
The third photo shows flowers in both stages, side view. The apparent petals are actually sepals, the actual petals of the flower are small things which fall out of the flower when the anthers go.
The Rhododendron hybrid cultivar 'Vinecrest'. In its parentage are R. fortunei which is a large tree-forming species, and an early-blooming small-leaf dwarf type from which the yellow flowers come. Fragrant too, with gorgeous constantly changing hues of salmoney-apricot (not a lunch recipe! although maybe... hmmm, I wonder...) buds seeen at the bottom of the photo, to fragrant soft yellow blooms. It is the earliest of the my large-leaf Rhodos to flower by a long shot, and gets its size from the tree side of the parentage. Definitely worth seeking out.