I've done something similar and it does work. It's good that you used mesh as it will give the moss something to attach to since it's hard for it to attach to smooth stones. Are you planning on keeping it trimmed to the shape of the rocks? That would look nice. If you do make sure you have a net handy to net out all the cut pieces. You'll have less floaties in the tank if you net them out right away.
I use door screen and suction cups to make moss walls. Currently using Flame Moss. Will post once mature.