TL350 picture of butterfly using smart mode

I took this picture with my TL350 camera set to Smart Auto mode. I was pleasantly surprised to see that the background is blurred a bit, but I didn't expect the camera to configure itself to be able to do this in smart auto.

My question, is if I wanted to set the camera up for this shot manually, would it have been better to use aperture mode to lock a big aperture for small depth of field, or is this simply a matter of using macro mode?