They were all taken with only nature lighting, aperture were set at F4 to F5.6 using either the Canon 100 F2.8 Usm Macro or the 70-200F2.8LIS on tripod. I never remember to bring my remote shutter cable that I bought 4 months ago. Large aperture setting will give you more blur in the background, just sufficient blur will be good enough, too much will flatten the picture.
I enjoy shooting flower more, may be it is easier to capture than human is.