Pesticides and herbicides, or weed killers, often contain harsh chemicals. The cost of purchasing commercial weed killers can become a large expense over time. Learning how to make homemade weed killer helps lawns and gardens thrive without spending a fortune on chemicals.Most homemade weed killers are non-selective, meaning the weed-killing solution also kills beneficial and desirable plants. Apply weed killers carefully, so liquids or powders only touch the weeds. Fortunately, homemade weed killers do not saturate soil or plant roots. The ingredients do not hang around long after application.
Vinegar in Homemade Weed Killers
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 in Homemade Weed Killers
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.
Benefits of Soap in Weed-Killer
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 and Baking Soda
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.
Simple Vinegar Weed-Killer Recipe
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 and White Vinegar Weed Killer Recipe
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.
Essential Oil and Vinegar Weed Killer Recipe
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 and Citrus Weed Killer Recipe
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 Weed Killer
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.
Bleach Homemade Weed Killer
A solution of 95% water and 5% bleach kills almost any weed, but it is a very harsh mixture. Use a milk carton with the bottom cut out of it to apply bleach solution, so the liquid does not splash nearby plants. Store bleach and water solutions in glass bottles because some plastics melt if they are exposed to bleach long-term. Bleach should only be used for extremely hardy weeds and must be used with care to avoid damaging lawns or gardens.