One of the issues here is that you tried to enclude way too much into each image, the results are DOF issues, poor compositions, and even some soft focus issues.
Pic #1, your DOF is way to great. Leaving the viewers eye to wander from the subject throughout the entire image. There is nothing other then the height of the plant to draw us back to it. You also have the horizon running dead center across the photograph. In pic #2, you lowered the horizon to the lower 1/3, forcing our eyes to the subject. The sky has some nice detail with those clouds, but is secondary to the subject. The issue I have with this picture, is that the focus seems soft as you go down the stem of the main flower, yet the background isn't out of focus enough. Picture #3 is a very nice composition, but again your DOF is so great that the flower buds lower in the frame, yet equal to the taller stalk is OOF. Also I'm not found of the fact that the stalk is pushed so tight up against the right side of the frame. You have more then enough room to have left a little breathing room. Picture #4 has correct exposure, and your DOF works well within your image. This time you centered the image dead center. Was there a reason you decided to do this? The exposure suffers from the bright & contrasty light. Nothing you could do for that, but it hurts the overall softness of the flowers. Also creates a lot of shadows within the flower itself. I would have repositioned the flower to the right to add interest, and it becomes a more pleasure image to view. If you can re-edit this one, please do so.
Taking florals mid day in bright sunlight is a very difficult thing to accomplish. Try for overcast days, and or go out early in the morning or late in the afternoon. Lately, I seem to fight these very conditions time and time again.