I've read a lot of posts about using newspaper as a earth-friendly weed barrier in gardens, but our project is a 32x36 ft playscape area in which we will be using pea gravel as our filler. The area around the playscape is just weeds right now, so although we've leveled the ground (and thus the weeds) I fully expect them to grow back with a vengeance. Does anyone have any experience with keeping weeds out of an area without a garden and any advice on what works best?

We also have a rocky area where our garbage cans are parked, but the grass has already started to take it over, so now I'll have to shovel out the rocks to get to the weeds...do not want to have to do this with such a large playscape area...EVER. (That's probably wishful thinking on my part, I know ;) Any help would be appreciated! Thanks.