there is just too much going on in the background...and I would have shot this with just one leaf...but that´s just me...otherwise it is good...keep going and soon you will be great...
Sunflowers are always good for an attractive image, but I feel you failed here. Some more thought into composition, background, light would be needed. Now it is just a flower in a vase on a table, nothing more. Sorry.
Very nice color. Interest is also nice. Clarity could be higher, background is a bit distracting, rotation to the left a tiny bit might help. Water reflection also a bit distracting. composition is nice.