Hi bluegrassmom-
I am a novice photographer, working hard to "up my game". The blurred background is obtained by several things, mainly using a lower numbered f-stop (which means a larger aperture or hole). But It ALSO requires a better camera with a larger sensor (bigger, heavier and more expensive). The tiniest sensors are in our cell phone cameras, you will notice that in them if you take a picture of that rose in your garden, you will also have the mailbox down the street in focus too! Sometimes this is desirable, but for an individual flower not so much. Generally, as cameras get bigger and more expensive they have bigger sensors, so you have the option of blurring the background out if you want to. For this you either go into manual mode and do all the settings yourself like an old fashioned camera, or you can put it in the semi-automatic "Aperture priority" mode and set the aperture (f-stop), letting the camera do the rest.
I took an evening class from a Nikon rep here in Seattle, about my particular new camera. I asked her if there were any good online classes or photography teachers around here. She thought a minute then recommended John Greengo, who has online classes at CreativeLive. I bought a course and have been working my way through it, I think he is an excellent teacher and it is reasonably priced. This is really technical stuff, and the video format (you watch it on your computer while online) is just great, you can pause and go back over any difficult concept until you get it.
I am also right now taking a class at my local Community College. The instructor gave me some great advice- go to flickr.com and get your free account. You can look at photos people have uploaded there. You can even search out photos taken by a particular camera (like yours) to see what can be done with it. Wait, that's not all! Many people have allowed the site to show what settings their camera was on for that photo, with what lens they had, the f-stop and ISO and shutterspeed. This is incredibly helpful to see how much was in focus and how blurred the background. Some of the photographers are pros so this is a great learning experience.
Hope this helps!