I would never use artificial mulch. What will happen when you have to dig, divide or pull out something? It will be a big mess.
Just use cedar mulch, that should last a long time and put it about 4 inches thick and then plant only things that will be hardy and not need a lot of pampering and water.
You may even consider some large stones, a statue, some tall grasses, things that look nice, but don't require water much.
