Many popular homemade week-killers contain distilled or apple cider vinegar. Most vinegar contains a 5% concentration of acetic acid. It kills weeds because acetic acid is a desiccant that removes moisture from plants. Horticultural vinegar contains 20% acetic acid. It is a much stronger weed killer than household vinegar, but it is also much more corrosive. Use caution with horticultural vinegar and wear goggles and protective clothing while applying it.

Salt is a popular weed-killer ingredient because it is a stronger desiccant than acetic acid. Rock salt or water softener salt works best in vinegar-based weed killers. Salt draws moisture from plants, but it has no impact on roots. Use only small amounts of salt in homemade weed killers. Large amounts of salt linger in the soil and kill anything planted in the area.

Soap increases the absorption rate of homemade weed killer. Liquid soaps such as detergent or dish-washing soap work best. The soap breaks down the waxy surface of weeds, so the weeds become more susceptible to other ingredients in the weed-killing solution. An additional benefit of soap is a distinctive appearance or scent that makes it easier to see which areas have been treated with weed killer.

Lemon juice contains acid that desiccates weeds. Saturate weeds with lemon juice using a spray bottle. Weeds die approximately two days after they are sprayed with lemon juice. Homemade weed killers containing lemon juice and vinegar have stronger desiccant properties to kill hardier weeds or eradicate weeds faster than either ingredient could alone. Apply baking soda directly onto weeds and make sure to coat the entire plant. Baking soda does not harm bugs, but it does kill plants of all kinds. Use baking soda only on days without wind or rain to avoid spreading the powder to wanted plants.

Make a gallon of vinegar-based weed killer with this simple recipe. Pour 1-gallon of apple cider vinegar into a large mixing can. Add 1-cup of salt and 1-ounce of liquid soap to the vinegar and mix well. Do not add any water because water weakens the weed-killing properties. Add citrus oil, bourbon, or gin to change the smell or enhance potency.

Capsicum is more commonly known as red or chili pepper and comes as a liquid or powder rub, and either form works in the recipe. Start with 3-cups of distilled white vinegar in a large mixing bowl or container. Add 3/4-cup of salt, 2-teaspoons of liquid dish soap, and 3-teaspoons of capsicum. Stir the mixture until everything is dissolved, and pour it into a spray bottle. This kills some types of ants as well.

Many people like to use essential oils in homemade weed-killers. This recipe fills a 16-ounce spray bottle. It includes 3-drops each of clove, wintergreen, cinnamon, and orange essential oils. Mix the essential oils and 2-ounces of liquid soap into 14-ounces of distilled white vinegar. Shake the spray bottle vigorously before each use so the oils spread throughout the solution.

Coconut oil serves the same purpose as soap. The oil breaks down the waxy coatings many plants use to protect themselves. Add 1-cup of coconut oil to 1-gallon of apple cider vinegar. Coconut oil does not dissolve easily into vinegar, so heat the mixture while stirring continuously. The mixture is ready to come off the heat in about 10-15 minutes when it has a uniformly smooth consistency. Add 3-drops each of lemon, lime, orange, and grapefruit essential oils. Wait for the mixture to cool then pour it into a spray bottle.

Cinnamon has herbicidal properties as an essential oil or as a powdered spice found at the grocery store. Mix 1-gallon of white distilled vinegar with 1-tablespoon of liquid dish soap. Add 15 to 20 drops of cinnamon essential oil or 1/4-cup of powdered cinnamon to the vinegar mixture. A few drops of citrus essential oils may enhance the strength of the weed killer. Pour the mixture into a spray bottle and saturate weeds.