Sorry I am late on this post. I find depth of field really washes away what has the high potential of distraction. This is displayed well here. When shooting flowers, especially outdoors and preferably real .. hehe just messing .. I like to incorporate the primary color of the flower into the blurred areas in front and behind the subject. In my mind opinion this adds interest and hints that there is more going on but in a subtle way. I nice contrast between light and dark is a huge plus. This concept is represented well in your last two photos. It would be interesting to see this last photo of the plant on the coffee table from multiple angles as to play on the lighting in the room a bit.
What camera type are you using here?
I like to shoot macro pointing the lens into a light source in order to really darken the background up without the use of photoshop type product...
I love experimenting like that. Not straight into the the light..sun in this instance..just off slightly as to not go blind. haha.
Best of luck!
RE: Beginner Questions on Photography