- 1). Cut a black plastic sheet slightly larger than the dimensions of the garden or flower bed in which you want to kill weeds.
- 2). Rake the garden or flower bed to remove any existing weeds, dirt clumps or other objects that may prevent the plastic from fitting closely over the soil.
- 3). Water the soil so that the top 12 inches of soil are damp.
- 4). Stretch the black plastic sheet over the garden or flower bed.
- 5). Set bricks, rocks or other heavy objects around the edge of the plastic sheet to hold it down.
- 6). Cover the edges of the plastic with soil.
- 7). Allow the black plastic to cover the soil for four to six weeks. The best time to do this is in the summer, where the soil will absorb the maximum amount of sunlight.
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