The lowest aperture for that lens is F4.5. I really wanted the background as blurry and smooth as possible. I wanted good bokeh although it at times becomes hard to achieve for me.
Nice flower Sunlou! It would be hard when your dog is trying to eat it. The only tip I can give you is maybe try to focus on the center as if looking down the middle of it. I don't know if you own photoshop or an image editing software, but sharpen it a little and rase the saturation a bit to bring those colors out. I don't know if you use the macro feature on your camera, but use that if you havent. Those features work great on point and shoots! That can give you possibly better bokeh.
-Christopher