I keep both files in the same folder (as Jen says they are different file types) if I think I may one day want to use the file again .. enlargement for print/framing/etc. If it is a photo that is a once use for a scrapbook page then I just keep the jpg once I have made any edits. I rename all my edited photos to "crop file# date" ... so in my monthly photo folder I have the edited jpg, the original jpg, and the raw if I keep it.
Photog Gear: Canon 70D, Canon 60mm, Canon 200mm, Canon 100-400mm II, Tamron 28-75, Sigma 150-500mm
Software: PSE 12, Lightroom 5