The ingredients that go into making the best organic, non-toxic weed killers have been around for many, many years. Way before the production of chemical herbicides, in fact, which didn’t begin until the 1940s.
Using non-toxic herbicides is the best way to kill and prevent weeds without harming the environment. But there are so many factors to consider and questions over their effectiveness that buying a container of RoundUp often seems like the easier option.
That’s why I’ve taken the time to research the best organic and non-toxic weed killers and compiled everything you need to know into this article. Each product has been tried and tested in order to determine which works best and under what circumstances.
Risks Of Toxic Weed Killers
Many active ingredients in chemical weed killers, such as glyphosate and paraquat — if not used correctly — can have harmful effects on humans, animals, and the environment.
They might be great at killing weeds but they’re also potentially damaging to humans, wildlife, and environmental health if allowed to seep into the soil and potentially into groundwater. That’s why manufacturers go to great lengths to provide comprehensive instructions for use and these should also be read and understood before attempting to use them.
Risks To Humans and Children
Herbicides pose a threat to humans before they ever enter the soil. Like any other chemical-based substance, herbicides can irritate your skin, irritate your eyes and lungs, or cause severe illness or death if ingested.
Two of the most commonly used ingredients in herbicides, glyphosate and paraquat, can have detrimental effects on both adults and children.
Glyphosate is one of the most popular ingredients in weed killers but has long since been banned in organic farming. It is crucial to avoid breathing in or exposing your skin and eyes to glyphosate because it can lead to chemical burns and irritation.
Paraquat is another commonly used toxic chemical in weed killers. According to the CDC, exposure or ingestion of paraquat can lead to a variety of chronic ailments and symptoms, including:
- Diarrhea and vomiting
- Kidney failure
- Liver failure
- Lung damage
- Heart arrhythmia and failure
Risks To Dogs, Cats, and Wildlife
While humans can avoid toxic weed killer exposure, for the most part, our pets and wildlife do not have the same luxury.
Chemical active ingredients in herbicides are toxic to pets and animals at much smaller doses than they are toxic to humans. If a dog, cat, or another animal ingests a plant that was treated with a toxic herbicide, it’s likely to experience serious symptoms.
Because most herbicides contain oil that helps them stick to target plants, these chemicals can be fatal to fish, algae, and other aquatic wildlife.
Toxic chemicals and weed killers seep into the soil and groundwater, which poses a long-term threat to our environment. Any runoff from these chemicals can pollute larger bodies of water, which can, in turn, kill aquatic organisms and poison our water supply.
Treating plants with chemical herbicides also builds up the plant’s tolerance to the chemicals, creating genetically altered plant species that become invasive very quickly.
Persistent toxic herbicide use leads to a buildup of chemicals in the soil. This build-up can kill or damage microorganisms for decades to come. Without healthy microorganisms in the soil, nutrient levels will deplete quickly, making the soil incompatible with life.
What Is the Safest Herbicide?
Humans have used the ingredients found in organic and non-toxic herbicides for millennia without damaging their health or the earth around them. That’s because these are often naturally occurring and therefore safe and organic.
With today’s technology, herbicide production has increased. Some of these products are not necessarily organic but may be non-toxic and safer for humans and our environment.
Non-Toxic Active Ingredients
Here are some of the most commonly used active ingredients that are used in non-toxic and organic weed killers:
More commonly known as vinegar, acetic acid is the most common active ingredient in non-toxic weed killers.
Household vinegar usually has a concentration of around 5%. According to the University of Maryland, concentrations of 15% or higher are usually most effective at killing targeted weeds.
While low concentrations of vinegar are safe to handle without any personal protection equipment, you should wear gloves and avoid breathing in the chemical when you are dealing with high concentrations of 20% or more as a precaution.
Citric acid is a non-selective herbicide that works best when combined with another acid, such as acetic acid. Citric acid-based weed killers are very effective at killing any plant they come into contact with.
You can find citric acid organically in the form of lemon juice. Combining lemon juice with household vinegar can be an effective herbicide but avoid using it as a weed killer treatment for your lawn because its non-selective nature means it will kill turf grass as well as unwanted weeds and plants.
Clove oil is a plant-derived essential oil and is a great selective herbicide for broadleaf weeds. Clove oil works by destroying the cuticle of the leaf. This then causes cell leakage that ultimately leads to the weed’s demise.
Clove oil isn’t found in many store-bought herbicides,but you can make a clove oil herbicide solution at home by adding 10 to 20 drops of clove oil into an empty spray bottle with either water or household vinegar.
Cinnamon oil provides a natural way to not only kill weeds but also repel pests. For best results, you should add 15 to 20 drops of cinnamon oil to a spray bottle filled with vinegar.
Apply this solution liberally to any weeds you are looking to get rid of. Cinnamon oil is very potent, so be cautious not to apply this solution to plants that you wish to keep around.
Lemongrass oil acts as both a pre-emergent herbicide and a post-emergent herbicide. It best targets perennial broadleaf and grassy weeds.
Lemongrass oil actively kills fungi and bacteria, so it is great as an herbicide and can benefit your existing plants. Its antimicrobial properties are what make lemongrass oil such an effective weed killer.
To use lemongrass oil as an herbicide, you can add up to 20 drops of the oil to either water or vinegar. Then, apply the solution either to the ground before the weeds have sprouted or two the weeds themselves.
Eugenol (a compound derived from clove oil) is becoming an increasingly popular ingredient for name-brand weed killers to use in place of toxic chemicals.
Eugenol is an excellent non-selective herbicide. It works by absorbing into a leaf’s cuticle and destroying it or by infiltrating the cell wall and causing leakage, which is ultimately detrimental to the weed itself.
Eugenol is not only a great natural herbicide, but it also repels pests like fleas, ticks, aphids, and other common garden insects.
Sodium Lauryl Sulfate
Sodium lauryl sulfate is the most common active ingredient in soaps and detergents. While this is not an organic option, it is a non-toxic option.
When applied to adult weeds, sodium lauryl sulfate strips the weed’s leaves of their protective wax coating, which ultimately leaves the plant exposed to the elements and results in the plant’s death.
Sodium lauryl sulfate works best when applied to smaller target areas and used as a spot treatment. This is because you can take the time to target specific weeds instead of accidentally applying them to healthy plants that you wish to keep.
Non-Toxic vs. Organic Weed Killer
While many people think that the terms non-toxic and organic go hand-in-hand as far as weed killers are concerned, there’s a big difference.
Non-toxic weed killers still contain chemicals like sodium lauryl sulfate, acetic acid, or citric acid. These chemicals, however, are safe and pose a minimal threat to humans and the environment.
Organic weed killers are those that come directly from nature itself. For example, clove, cinnamon, lemongrass, and eugenol are effective herbicides when in essential oil form. Organic herbicides are often — not always — non-toxic.
Non-Toxic and Organic Herbicides Reviewed
Having now reviewed the high points and risks of both toxic herbicides, non-toxic and also organic ingredient alternatives, here’s my pick of the best non-toxic weed killers that are available on the market today. I’ve based my results on personal experience as well as scouring forums and review sites to bring you the highlights.
1. Natural Elements Weed Killer Pet Safe Herbicide
This biodegradable, non-toxic weed killer from Natural Elements uses water, vinegar, salt, and sodium lauryl sulfate to help keep your yard weed-free and is intended to be less harmful to the environment.
It can be used for ridding your yard and garden of both broadleaf weeds and invasive or unwanted grasses and it gets to work with visible results in as little as 24 hours.
This is a non-selective post-emergent, so only use it in areas that you want clearing and avoid applying it to areas containing grasses and plants that you want to keep around.
I like that this weed killer product comes premixed and ready to use, so there’s no need to add water or make any other preparations. All I had to do was transfer the liquid into a handheld sprayer and simply spray over the weeds I wanted to clear. This size is perfect for larger-scale areas that need clearing.
It’s a great choice if you have kids or pets since it doesn’t contain those potentially toxic chemicals that can do so much damage if touched, sniffed, or ingested. Do read the instructions though because this product needs to be stored carefully and is not safe for human consumption and may cause some irritation if its gets on skin or in the eyes.
- Not harmful to the environment
- A safer choice if you have children or pets
- Only suitable as a non-selective herbicide so avoid using around plants, trees and shrubs you want to keep
2. Just for Pets Weed Killer Spray
The brand Just for Pets has got it nailed when it comes to looking after pets. Their weed killer spray contains only natural and organic ingredients including acetic acid, citric acid, salt, clove oil, and lemon juice.
Because there are no chemical nasties contained in their weed killer, pets are safe to roam over areas that it has been applied to just as soon as it has dried. What’s more, they donate a proportion of their profits to pets charities throughout the US.
This is a non-selective, post-emergent herbicide which means you should avoid applying it to your entire lawn or anywhere you have plants you wish to keep. It’s great for clearing areas or as a spot treatment on pavers and driveways or pathways.
The other good news is this non-toxic weed killer needs no pre-mixing or diluting and comes with a robust spray nozzle attachment for extra easy application.
- Kind to pets and the environment thanks to its all-natural and organic ingredient list
- Safe to walk on as soon product has dried
- Non-selective so unsuitable for use on lawns and borders
3. Green Gobbler 20% Vinegar Weed and Grass Killer Natural and Organic
Green Gobbler 20% vinegar weed killer is a non-selective, post-emergent herbicide. Its active ingredient is 20% acetic acid, which is four times stronger than household vinegar. This weed killer is also certified organic and is made using corn extract.
This jug of Green Gobbler comes with a trigger sprayer and is ready to use, so I didn’t even need to dilute it. Because this herbicide is non-selective and post-emergent, it’s crucial that you not apply it to your entire lawn or garden. I found this most effective as a spot treatment weed killer for the pesky and unsightly weeds that grow amongst the cracks and through gravel drive. In my case dandelions, clovers, and crabgrass.
Unlike other toxic herbicides, you can expect to see results from Green Gobbler in 24 hours or less. I discovered that for best results, avoid applying this weed killer when rain is in the forecast. Green gobbler works best when it can soak into the plant and dry it up without water interfering.
- Effective spot treatment for many common broadleaf weeds and grasses
- Ready to use and suitable for smaller areas
- Only suitable for use in dry conditions
4. Energen Carolina Vinegar Organic Weed and Killer Pet Safe
The Energen Carolina weed killer is a vinegar-based herbicide that is most effective at killing broadleaf weeds and grasses such as crabgrass, clover, dandelion, and ivy. It is organic a certified organic weed killer that is derived from corn, so there’s no need to worry about toxic chemicals polluting your yard or garden either.
Energen Carolina is a non-selective, post-emergent herbicide that is safe to use in residential, commercial, and agricultural settings and can also be used safely around children and pets providing the manufacturer’s instructions are followed.
The acetic acid in this weed killer works to dry up target weeds in as soon as 24 hours. I discovered that for best results, do not dilute the product and add it to weeds when the ground temperature is between 50 and 75 degrees Fahrenheit.
- Certified organic and therefore free from toxic chemicals
- Can be used without needing to be diluted
- Not safe for use on ornamental lawns, flower beds, veg patches or other plants and trees you want to keep
5. Natural Armor Weed and Grass Killer All-Natural Concentrated Formula
Natural Armor is a known and trusted brand in the weed killer community. Even though they most popularly produce weed killers that contain toxic chemicals, they stepped up their game to produce this weed and grass killer that is all-natural and non-toxic.
This is a fast-acting, non-selective post-emergent that kills weeds in as little as 24 hours and it comes in a ready-to-use formula with a spray nozzle so there is no need for messy mixing and diluting.
I liked that this product is available to buy in various sizes, ranging from 16 oz to 2.5 gallons, so it fits a variety of needs depending on the area you are looking to cover.
For best results, you will need to apply this on a sunny day with little or no breeze when the ground is 65 degrees Fahrenheit or warmer. You’ll also need to make sure there is no rain in the forecast for the next couple of days.
- Available in a range of sizes for different coverage areas
- Ready to use and complete with spray nozzle attachment for ease of use
- A great choice and one of the best weed killers for lawns
- Needs specific weather conditions in order to be effective
6. Harris Vinegar Vinegar Organic Weed and Weed Grass Killer
Harris is another known and trusted name in both the herbicide and pesticide community. Instead of using toxic chemicals like glyphosate, this weed killer contains only organic and non-toxic ingredients such as acetic acid which is 4 times stronger than household vinegar.
Reviewers were impressed with results noticing targeted weeds beginning to dry up and brown in as little as 24 hours or less although stubborn weeds may need a second application. Some felt that the odor of vinegar was rather stringent although quite a good deterrent for cats and dogs.
This herbicide is non-selective, so be mindful while applying it to your lawn or garden.
- Does not contain glyphosate
- Fast acting results in as little as 24 hours
- Strong smell of vinegar
7. Calyptus 45% Pure Super-Concentrated Vinegar
This all-purpose vinegar-based product from Calyptus has a multitude of purposes for both the home and in your yard. The 45% super-concentrated mixture is said to be 9 times stronger than household vinegar and is effective at removing dirt and limescale, as well as helping to eradicate weeds in your yard.
This non-toxic product is versatile enough to be used as an effective cleaning agent when applied neat and can also be diluted and combined with salt and a surfactant to assist with weed removal.
I tried this out as a diluted solution on some newly sprouted broadleaf weeds that had appeared on my pathway in spring. The results were impressive with a clump of dandelions wilting and browning within 24 hours. Stubborn and persistent weeds may need further applications to ensure root removal and always remember that this should be treated as a non-selective, post-emergent so never apply it to areas that you wish to preserve.
- Versatile range of uses in both the yard and home
- Super concentrated formula to increase effectiveness
- Needs to be combined with other household products for maximum effectiveness at killing weeds
8. Espoma Weed Preventer Plus Lawn Food, Natural Lawn Food
Unlike the other products I am featuring in this review, Espoma Organic Weed Killer is a selective, pre-emergent weed killer meaning you can use it to prevent weeds ever appearing in your lawn without ruining it.
This weed killer is similar to the others in that it is non-toxic and organic as well as all-natural. It works brilliantly as a dandelion killer as well as preventing many other common weeds such as crabgrass and clover from ever becoming a problem in your lawn. It’s the inclusion of 100% corn gluten meal that works to prevent the development of dandelion roots.
Not only that, this product doubles as a lawn fertilizer thanks to the inclusion of slow-release nitrogen that helps to fertilize your lawn and ensure the vitality, healthy growth, and lush green color of your lawn.
For best results, apply the granular mixture twice a year in early spring and early fall to cover your lawn. Water thoroughly after application. product into the ground after application. It’s also completely safe for pets and children to play in the yard, even directly after an application.
- Effective as a pre-emergent
- Also fertilizes lawns
- Not suitable for use on already sprouted weeds
When To Use Organic and Non-Toxic Weed Killers
I found that the post-emergent weed killers on my list provided me with the best results possible when I applied them on clear, sunny, warm days.
You can use non-toxic herbicides year-round as needed,but it’s recommended that you wait until the soil is at least 50 degrees Fahrenheit and that there is no rain in the forecast for a few days.
Tips For Applying Organic Herbicides
Applying non-toxic post-emergent weed killers to your lawn is easy to do. Almost all post-emergent products come pre-diluted and pre-mixed, so all that you need to do is add the product to a sprayer or attach the provided spray nozzle and apply it to your yard.
With post-emergent products, make sure to apply on a warm, sunny day when there is no rain in the forecast so that the product doesn’t get washed away before it has time to work.
With non-toxic pre-emergent weed killers, the application process is slightly more difficult but still not hard to do. Pre-emergents need to be watered into the soil so that they can get in contact with the seeds and prevent them from sprouting.
To apply a non-toxic pre-emergent to your yard, sprinkle the product across the target area either with a grass seeder or by hand, and then spray your yard with water.
Types of Weed Killers
To decide which herbicide will work best for you, it is important to understand the different types of weed killers.
Weed killers and herbicides are not universal. There are different types of weed killers, like selective, non-selective, pre-emergent, and post-emergent.
Selective vs Non-Selective
The terms selective or non-selective apply to the weed killer’s ability to target specific weeds. Manufacturers’ labels will always provide details of what weeds can be killed using a selective herbicide. Non-selective herbicides are, well, non-selective, meaning they will kill anything they come into contact with.
Selective herbicides target and inhibit the growth of specific weeds while not causing any damage to other surrounding plants.
Non-selective herbicides do not target specific weeds. When applied to a general area, non-selective weed killers kill every plant — weed or otherwise — in that area. For this reason, non-selective herbicides are also referred to as “broad-spectrum” herbicides.
Pre-Emergent vs Post-Emergent
Herbicides will kill weeds either before they sprout or after, which is why understanding the difference between pre-emergent herbicide and post-emergent herbicide is crucial.
Pre-emergent herbicides are great for solving a weed problem before it ever even starts.
When applied to the target area, pre-emergent herbicides enter the soil and kill weeds before they have the chance to erupt from the ground.
Pre-emergent herbicides either coat a seed’s protective layering and prevent it from sprouting altogether, or they inhibit enzyme production within a sprout and kill the weed before it breaks ground.
On the other hand, post-emergent herbicides are herbicides designed to kill weeds after sprouting and establishing themselves.
Post-emergent herbicides usually work by damaging a leaf’s cuticle or by entering the leaf’s cells and causing leakage, both of which are fatal for the plant.
Alternative Homemade Weed Killers
You don’t have to spend a fortune on a fancy herbicide from the store to kill weeds in your lawn and garden effectively. Many accessible household items can act as a non-toxic alternative to chemical herbicides.
Salt is one of the most accessible homemade weed killers. Salt is a great non-selective, non-toxic option that does a great job at killing the weeds it’s applied to.
Applying a salt solution to weeds will give them a surplus of sodium chloride, which poisons and kills the plant.
To use salt as an herbicide, mix a solution of three parts water and one part table salt. Apply this mixture to the target area every day, increasing the salt concentration as needed.
Once the weeds begin to show signs of damage, stop applying salt because too much salt over time can damage the soil.
Corn meal, specifically corn meal gluten, is an effective household pre-emergent herbicide.
When applied to your lawn or garden, corn meal gluten will prevent any seeds present in the soil from sprouting. Corn meal dries out the seed’s protective coating, causing it to die before it has the chance to sprout.
Corn meal is also fantastic for controlling pests, especially ants.
Rubbing alcohol is notorious for killing bacteria and viruses but it’s also a great homemade way to kill unwanted weeds in your pots and planters. Using rubbing alcohol on your lawn or in-ground garden isn’t recommended because it can contaminate the soil.
To use rubbing alcohol as an herbicide, add two tablespoons of alcohol to a quart of water and spray it on unwanted weeds. The alcohol will dry and wither the plant’s leaves, in turn killing the plant.
Another accessible household herbicide is vinegar. The active ingredient in vinegar is the same active ingredient as in some of the most popular non-toxic herbicides: acetic acid.
The acetic acid in the vinegar attacks the weed’s cells and causes them to burst and leak, which in turn kills the plant.
Vinegar is an accessible and affordable homemade weed killer. There’s no need to dilute it either, as most store-bought solutions have a concentration of around 5%.
All you need to do is spray the vinegar onto the target area and repeat every few days as necessary.
Baking soda is an affordable and effective homemade pre-emergent and post-emergent weed killer.
To use baking soda as an herbicide, you can either mix it with water and spray it on the target area, or you can simply sprinkle it over the target area.
Baking soda essentially dehydrates the weed by extracting water from its cells. This method is both quick and effective.
Pouring boiling water over the area where you want to get rid of weeds is the cheapest and most long-lasting homemade weed-killing method.
To use boiling water as a weed killer, all you need to do is pour boiling water over the target area. This will kill both seeds and roots, which can help get rid of your weed problem for good.
Verdict: Best Non-Toxic Weed Killer
In my opinion, the best non-toxic post-emergent weed killer on my list is Natural Elements Weed Killer. It is non-selective so it’s not safe for use on plants you want to keep but it does boast a wide range of target weeds. It also comes as a ready-to-use formula which means you don’t have to spend time with messy mixing and pouring.
My second choice is Just for Pets Weed Killer. This too is a non-toxic weed killer that is post-emergent and non-selective. The added bonus with this product is just how pet-friendly it is. Not only is it suitable for people and pets to walk on right after it’s dry but a proportion of this company’s profits also goes to pet charities across the US.
If it’s a pre-emergent you want, I highly recommend Espoma’s Weed Preventer and Lawn Fertilizer. Not only is it safe to use on your precious grass but it also doubles as a fertilizer. This one is best used in the fall right before weed seeds sprout and when your lawn needs a good feed after the growing season.