How to Kill Weeds Using Homemade Weed Killer

Picture a beautiful flower bed on a sunny summer afternoon. Clusters of blooming plants -- yellow, lavender and crimson -- nestle in layers of dark mulch. The breeze ruffles the plants' foliage, and something catches your eye: a weed. You crouch down and pull the weed, but then notice that a few more weeds have popped up. Several commercial products promise to prevent or kill weeds, but you may prefer a more natural, homemade approach.

Dandelions
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Weeds growing in a yard.

Vinegar and Salt

Kill Weeds
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Spraying weeds.

A combination of 1 gallon of distilled white vinegar, 1 cup of table salt and 1 tablespoon of dish soap in a plastic tank sprayer makes an effective homemade weed killer. The acidity in vinegar causes the leaves to break down when it is sprayed directly on any plant. It also depletes magnesium from the soil. Take care to avoid spraying on the plants you want to keep because this natural weed killer will damage or kill all plants it comes in contact with. Also, avoid spraying the same spot multiple times if it has not rained in a while. The salt in this weed killer could sterilize the surrounding soil if there has not been enough rain to wash it away.

Corn Gluten Meal

White quinoa on rustic wooden background
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A bowl of corn gluten.

Corn gluten meal suppresses seed germination, so it is ideal for preventing weed seeds from sprouting. Sprinkle the meal on garden beds that have no existing weeds. It's not a problem if the cornmeal comes in contact with the plants. Its weed-killing properties affect only seeds that might have been in the surrounding soil or mulch. If you have planted seeds in such an area, avoid applying corn gluten meal until after they have sprouted.

Molasses Solution

Treacle
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A bowl of molasses.

One weed in particular, Cyperus esculentus, or yellow nutsedge (sometimes referred to as nutgrass), grows relentlessly throughout the United States in U.S. Department of Agriculture hardiness zones 4 through 9. The yellow nutsedge is susceptible to treatments of molasses. Prepare a solution of 1 gallon of water to 1 cup of molasses and pour directly onto the nutsedge. After two or three applications, the nutsedge will shrivel and die, reports the Organic Authority website. An added benefit is that molasses acts as a fertilizer for most other plants.

Baking Soda

Close-up of baking soda on spoon.
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Baking soda being mixed with water.

For weeds that grow between pavement cracks or stepping stones, try sprinkling baking soda and sweeping it into the cracks. Baking soda contains a large amount of sodium, which will sterilize any soil and prevent anything from growing there. This treatment must be repeated after it rains. Avoid using too much, as it can affect surrounding soil if the baking soda accumulates.