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11 ways to control weeds without chemicals

Aug. 13, 2010, 11:07 a.m.
black plastic sheet

Photo: coun2rparts/Flickr

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Plastic sheets

Solid plastic sheets are alternative for covering the ground and blocking growth of weeds (and other plants). The plastic blocks water and light penetration, killing the plants underneath. This is also known as solarization

It is a fast and effective way to kill grass before replacing it with a vegetable garden or different type of lawn.

Lerner said there are many plastic sheeting colors, each of which have different uses.

“Black plastic tends to warm the soil, which is beneficial for warm-season crops, such as tomatoes and peppers,” she said. “White plastic also works well as a mulch, but it does not have as much effect on soil temperature as black plastic. Recent studies have found that other colors of plastic, particularly red, may enhance plant growth. Clear plastic should not be used since it allows light to penetrate, resulting in germination of weed seeds and excessive heating.”

Also, plastic is not a good way to avoid chemicals usage. Lanini notes that most plastic is derived from petroleum, and may be even less organic than chemical sprays.