There is a lot of confusion about mulch and rhododendrons and you deserve credit for trying to get it right! Here is what I learned and do in my own garden. I use a mulch of wood chips or beauty bark every five or six years but I \"feather\" this mulch around the roots of the rhododendrons and camellias. This means I use just one inch or less next to the trunk of the plants but layer the mulch deeper as I go out toward the drip line or leaf overhang of the shrubs so that it may be up to two inches deep at the edge of the leaf canopy. The mulch can be 3 or 4 inches deep between plants. This does create a bit of a depression at the base of each plant but this is barely noticeable and helps to hold and collect rain water - and we know how much rhododendrons and azaleas love moisture. I also clean out any dead or mossy bits from the center of my azaleas using a gloved hand so that sunlight and rain can reach the roots more easily. If your azaleas are not thick with dead twigs and moss you don't need to do this. Fine beauty bark with chunks smaller than your pinky finger are better than the big chunks for around the base of the plants but the more coarse beauty bark is better at keeping down the weeds. Keep growing, Marianne Binetti