I have heard a lot about how hard it is to keep weeds out of a rock garden and how that layering with thick plastic, newspapers, spraying with round up, etc. I have another suggestion that I plan to try and since I plan to plant my flowers, etc. in large pots instead of the ground, I will pour a layer of concrete in the area I want to pour my rocks on. This will keep out the weeds and even though it may be somewhat of a expence to start with, I won't have to worry about ever weeding. When I am finished I will post a pic of my beautiful rock garden without the weeding.