My favorite mulch is shredded oak leaves, because it is good and that's what I have a lot of. I use it fresh or decayed. I have also used cocoa hulls=good, garden smells like chocolate, but it washes/floats away real bad in the rain. Black dyed recycled wood=day after I put this down I found out that it is really bad to use, with possible pressure treated wood and other bad things inside. Hay or straw=too many problems with the seeds sprouting and turning into a major weed problem. Pine bark nuggets=I found it too chunky and it didn't decompose. Newspaper=doesn't look very nice, blows around in the wind. Compost=best, just I usually don't have enough to mulch everything. Whole oak leaves=I got lazy last fall and didn't rake one flower bed. Stuff came up no problem and I just left them down. They take a long time to break down I think. They weren't very thick, otherwise they would have matted down and been inpenetrable.