How to Make a Homemade Weed Killer (2024)

Trending recipes for homemade weed killer pepper the internet, but their effectiveness, eco-friendliness, and safety are often up for debate. Not only will we show you how to make a homemade vinegar weed killer that works, but we’ll also discuss the pros and cons of taking this homemade approach.

First off, that household vinegar in your kitchen cabinet might not be strong enough to tackle the lawn weeds. You’ll likely need vinegar with a higher acetic acid content. And you can leave behind the borax and conventional dish soap that some vinegar herbicide recipes call for (these ingredients aren’t so eco-friendly).

Ready to make an effective vinegar weed killer? We’ve got you covered.

How to Make a Vinegar Weed Killer

The trick to creating an effective homemade weed killer is using vinegar with the right acetic acid content. The acetic acid affects the cell membranes of any plant it comes in contact with, effectively damaging foliage tissue. The vinegar works by desiccating, or dehydrating, the foliage tissue on contact.

Household vinegar is 5% acetic acid, but this concentration of acetic acid is only strong enough to kill young weeds with one to two leaves. According to the University of Maryland Extension, weeds with three to four leaves are likely to survive acetic acid levels between 5% and 10%.

To control the large weeds in your lawn and vegetable garden, use a horticultural-grade vinegar with higher acetic acid concentrations (no more than 20%).

Here’s a DIY vinegar herbicide recipe listed on the Northwest Center for Alternatives to Pesticides’ website. Combine these two simple ingredients in a garden sprayer with the following ratio:

• 1 gallon of vinegar containing 5% acetic acid or more (but no more than 20%).
• 1 cup of castile soap. (Castile soap is a vegetable-based soap free of animal fats and synthetic ingredients. The soap allows the vinegar to cling to the plants.)

Pro Tip: Weeds wilt even faster if you spray on a sunny day.

Pros and Cons of Homemade Vinegar Weed Killer

Homemade herbicides are popular among people who want to avoid spraying synthetic chemicals on their lawn and garden. While it’s possible to find an all-natural herbicide recipe, some recipes aren’t as “natural” or “organic” as they claim to be. In other words, vinegar weed killer recipes have many benefits, but it’s good to be aware of their shortcomings, too.

Pros of Homemade Vinegar Weed Killers

• If you need to control only young weeds with one to two leaves, the household vinegar in your kitchen can provide effective control, saving your wallet a few bucks.
  
• Homemade vinegar herbicides containing no synthetic chemicals are an eco-friendly alternative to synthetic herbicides sold in stores.
  
• Vinegar containing 5% to 10% acetic acid can control young weeds, while higher concentrations (up to 20%) can effectively control larger weeds.
  
• Acetic acid is biodegradable, which means it breaks down in the environment and won’t build up in your soils, unlike synthetic chemicals.

Cons of Homemade Vinegar Weed Killers

• Some homemade herbicide recipes misuse the terms natural, organic, safe, and eco-friendly. For example, some vinegar weed killer recipes list conventional dish soap as an ingredient. However, most dish soaps contain synthetic chemicals that aren’t good for the environment.

  Borax is another common ingredient in homemade vinegar herbicides. It’s a mineral commonly used for cleaning, yet mining for borax leaves behind a large environmental footprint. Borax is also poisonous, especially to young children.

• Household vinegar isn’t strong enough to kill larger weeds. You’ll likely need to buy a horticultural-grade vinegar at your local garden shop. Most horticultural vinegars are 15% to 20% acetic acid.
  
• Handling vinegar comes with risks. Vinegar with an 11% or higher acetic acid content can burn the skin and cause eye injuries, including blindness.
  
• Vinegar damages only foliage it comes in contact with. The root system is protected underground and remains unharmed, sprouting new weeds after vinegar applications. Dandelions, for instance, are challenging to eradicate naturally due to their long taproots growing new dandelions.
  
• Vinegar is a contact herbicide, which means it will damage any plant it comes in contact with, including grass or other desirable foliage. Apply your vinegar herbicide with care.
  
• Homemade herbicide recipes (containing vinegar or otherwise) often won’t list safety hazards. Store-bought herbicide labels must list potential hazards and safety information.

Does Vinegar Weed Killer Really Work?

Yes, a homemade vinegar weed killer can be effective depending on its acetic acid content, the weed’s type and age, and how much weed killer is applied. Control might fail if you attempt to remove a large weed with household vinegar.

On the other hand, horticultural vinegar higher than 10% acetic acid can provide effective control against young and old weeds.

And, of course, you will need to apply your vinegar weed killer whenever you see interlopers sprouting in your yard.

Homemade Weed Killer vs. Store-Bought Weed Killer

Homemade herbicide vs. store-bought herbicide isn’t necessarily a case of good vs. evil. Eco-friendliness and safety are often associated with homemade herbicides, while harmful synthetic chemicals are associated with store-bought herbicides.

But it’s not always that black and white. Believe it or not, some store-bought weed killers are safer for you and the planet than some recipes you might find online.

In-store organic herbicides often contain chemicals that exist in nature and are easy on the environment. On the other hand, some homemade organic weed killer recipes call for synthetic ingredients, such as dishwashing soap, or ingredients poisonous when ingested, like borax.

So, should you treat your weeds with homemade vinegar weed killer or store-bought weed killer? Neither is necessarily better than the other, and both can achieve the same goal of being eco-friendly. Horticultural vinegar does come with safety hazards, but whipping up your own solution might save you a few bucks.

Pro Tip: When shopping in-store, look for organic weed killers certified by the Organic Materials Review Institute (OMRI).

FAQ About Vinegar Weed Killer

Hire a Pro for Easy Weed Control

Here’s the thing about vinegar and other organic herbicides –– they won’t always kill weed roots, which means the weed can resprout with ease. While a vinegar application kills the weed’s foliage, it’s not unusual to see a new sprout taking its place.

Attacking the same weed over and over is no way to spend your free time. Hire a local Lawn Love professional who can do the grunt work for you while you enjoy your yard weed-free.

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