Using temporary black plastic sheet mulch to kill weeds, clear land, and help create a productive vegetable garden. This is a technique used to create organic, no-dig vegetable gardens.
First, clear the area that you'd like to turn into a vegetable bed or entire vegetable garden. Cut the grass short, and dig up any shrubs or perennial weeds.
Next, it's best to spread two to three inches of organic compost on the ground. You can also spread the grass clippings, leaves, and any other finely chopped organic material. If you don't lay this layer, the ground will be bare soil when the process is finished and will need more work.
Spread the black plastic sheeting over the entire area you wish to clear. Having a second person to help will make this step easier, and I'd avoid laying the plastic on a windy day.
Weigh the plastic down at all four corners, along the edges, and throughout the center. Ensure that the wind won't pick the plastic up and send it sailing to the next county.
If you'd like to increase the amount of air and moisture reaching the soil beneath, pop small holes in the plastic with a pitchfork/garden fork. Doing this can help the soil biota beneath.
Leave the plastic in place for however long it takes to kill the grass and weeds underneath. In the summer, it may take only two to three months; in the winter, it can take double that. If you have a lot of tough weeds underneath, it may take up to a year.
Peel the plastic back, either all at once or in parts, to begin growing in your new growing space. If you've laid compost down first, the ground will be tilled by worms and soil bacteria and will be ready for planting.
Watch the video below to see how to use heavy-duty black plastic to kill weeds, alongside two other types of sheet mulch. Shows further before and after shots.
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Notes
If you'd like to clear land the organic way, this is the easiest way to go and the first step to how to start a new vegetable garden