I recently planted my vegetable garden using a product from Home Depot which is a black plastic sheeting (actually it may be woven of some sort of fiber material) It has a dull side and a shiny side. It is held down by 6 inch long staples that you push into the soil. It is supposed to prevent the growth of weeds. You cut an X in it to plant the plants. I have soaker hoses underneath it. Any advice on the proper use of this product? Is it necessary to cover over it with bark mulch or wood chips? Thanks. Jay S.