If you like the feeling of this photograph with the soft background and shallow depth of field then I recommend using your largest telephoto lens and getting as close as possible to the subject while still being able to maintain a focus. Then set your aperture to the largest opening. In this photo I used a huge 600mm lens wide open at F4 and I was only about 18 feet away from the tulip that is in the sharpest focus. F4 at 1/1000, ISO 100, 600mm lens at 600mm