As alternatives to traditional synthetic products, all-natural and organic weed killers eliminate weeds without compromising the health of your soil, turfgrass, or plants. If you’ve never heard of systemic, contact, pre-emergent, and post-emergent weed killers or didn’t know you could eliminate weeds with salt and vinegar, we’ll walk you through everything you need to know.
What are all-natural and organic weed killers?
All-natural and organic weed killers (herbicides) are solutions derived from natural or plant-based ingredients to gently eliminate weeds and other unwanted vegetation. As alternatives to synthetic or inorganic herbicides, they prioritize sustainability, plant and soil health, water quality, and ecological balance.
Many people use the terms “all-natural” and “organic” interchangeably, but they don’t actually mean the same thing. To earn the “organic” label, products have to satisfy a defined set of criteria set out by recognized organizations and institutions. All-natural weed killers are less subject to as many strict certification processes and regulations. As a result, these products may still contain hormones or artificial ingredients.
For maximum weed-killing potential, it’s recommended that you combine all-natural or organic weed killers with other weed-control strategies. These include:
- Applying mulch such as wood chips, compost, or straw around plants to suppress weeds
- Limiting the space between plants to discourage weed sprouting
- Hand weeding every once in a while
- Using pre-emergent and post-emergent herbicides
- Mowing your lawn according to your grass type (in terms of frequency and height)
- Monitoring your lawn and garden regularly
Safer options, such as all-natural and organic weed killers, contain some of the following active ingredients:
- Acetic acid (vinegar)
- Citric acid
- D-Limonene (citrus oil)
- Clove, lemongrass, or cinnamon oil
- 2-Phenethyl Propionate
- Sodium Lauryl Sulfate
- Eugenol
- Ammonium Nonanoate
- Pelargonic Acid+Fatty Acids
Pros of all-natural and organic weed killers
Organic herbicides align with eco-friendly yard maintenance practices and offer many advantages in fighting pesky weeds. Here are some pros associated with these alternatives:
- Environmentally friendly: The natural ingredients present in all-natural and organic products break down more easily, reducing the risk of long-term damage to soil, water, and other non-target organisms.
- Safer to use around pets and humans: Compared to synthetic herbicides, organic ones are less harmful to pets and people, creating a safer environment during and after use.
- Contribute to soil health: Organic weed killers keep your soil healthy by providing nutrients and improving microbial activity.
- Reduced risk of plant resistance: Organic herbicides are less likely to lead to herbicide resistance. This is because, once applied, multiple mechanisms come into play, making it challenging for weeds to develop resistance to all of them at once. These include destroying plant cell membranes and interfering with photosynthesis and protein breakdown necessary for plant growth and development.
- DIY: Many all-natural and organic weed killers can be made in the comfort of your own home, with household ingredients most people have on hand.
Cons of all-natural and organic weed killers
There’s no denying that all-natural and organic weed killers are great for the environment, but they have limitations and drawbacks, as well. Let’s take a closer look at what these are:
- Less effective on established weeds: Most organic herbicides derived from pure natural ingredients are less effective on already established weeds. They’re typically aimed at young, vulnerable plants in the early stages of growth.
- More time and effort involved: You’ll generally have to apply the herbicide multiple times to achieve the same results as synthetic options. This can increase the time and effort you spend eradicating weeds in your yard.
- May not eliminate all weeds: Most organic options are selective, meaning they work on some weeds and not others. They’re also more vulnerable to weather conditions, so consider the types of weeds you have before selecting a weed killer.
- Takes longer to get results: If you’re used to synthetic herbicides but want to make the switch to organic, be prepared for it to take longer to kill those stubborn weeds.
- Results don’t last as long: The benefits of organic herbicides are more short-lived than synthetic ones. This means you will have to apply them more often.
- More expensive: Organic herbicides purchased in-store can be more expensive than synthetic ones. This is due to their specialized ingredients and formulations.
Types of all-natural and organic weed killers
Weed killers (including all-natural and organic ones) are classified according to their mode of action. Based on your preferred attack strategy, you have some options at your disposal.
Systemic weed killers
Systemic weed killers take longer to provide the desired results. After being absorbed, they travel throughout the plant, targeting its internal systems, including the roots and shoots. The good news? With the root system out of the way, you won’t have to worry about the weeds sprouting back up again.
Contact weed killers
If you’re on the hunt for a fast-acting herbicide that acts primarily on the plant parts it comes into direct contact with, contact post-emergent is your best bet. Unlike systemic herbicides, contact herbicides affect only the areas where they’re applied. They’re valuable for their quick action and effectiveness when rapid vegetation control is necessary.
Pre-emergent weed killers
With pre-emergent weed killers, you can target weed seeds directly in the soil, preventing them from germinating and sprouting. They form a barrier in the soil that inhibits weed growth, thus saving you from unpleasant weed control down the line.
During application, maintain a satisfactory distance from desired plants, as these herbicides can interfere with seed germination in those, too.
Post-emergent weed killers
Post-emergent herbicides control weeds that have already germinated and emerged from the soil. Unlike pre-emergent herbicides, which stop weed seeds before they sprout, post-emergent herbicides are applied to actively growing weeds. Many homeowners use them to manage weed infestations in lawns, gardens, agricultural fields, and other landscapes.
DIY natural and organic weed control methods
You can buy organic weed killers in your local home improvement store, but you can also save time and money and make your own at home. Chances are, you’ll have all the necessary ingredients on hand.
Here are some examples of tried and true homemade weed killers:
Boiling water
Type: Contact, post-emergent weed killer
Many people use boiling water as a natural, chemical-free way to attack weeds. This method works on small yards and tender, young weeds or seedlings, especially those growing in or around pavement cracks, gravel driveways, and other hard surfaces. Boiling water is useful if you don’t want to kill surrounding vegetation.
How to use:
- Identify the types of weeds you have. Only use this method if the weeds are in the early stage of growth.
- Boil an approximate amount of water, depending on the severity of the weed infestation, and pour it over the problem area, making sure to saturate the entire plant. Pay particular attention to the base to ensure the water reaches the root system faster.
- Repeat this process as many times as necessary to kill the weeds.
Salt solution
Type: Contact, post-emergent weed killer
Salt also can be an effective, inexpensive, and environmentally friendly way to kill weeds growing in driveways, walkways, or between pavers. Why? It dehydrates plants and exhausts their energy supplies. When using salt to kill weeds, it’s important to exercise control; in large quantities, salt can harm your soil and desired plants.
How to use:
- Identify the problem weeds. Make sure they’re young.
- Gather your supplies: table or rock salt (free of iodine), warm water, and a sprayer or watering can.
- Based on the severity of the infestation (the more weeds, the more concentrated the mixture), mix the salt with the warm water. This can be 1 cup of salt to 2 cups of water, but the ratio can be adjusted as needed. Stir until the salt is completely dissolved.
- Pour the solution into the sprayer and apply it to the target weeds, saturating the foliage and insisting at the base.
- Repeat as necessary until the weeds die.
Vinegar solution
Type: Contact, post-emergent weed killer
Another popular DIY weed control method is vinegar weed killer. Vinegar can be mixed with various other household items, including baking soda, dish soap, and water, to achieve an effective weed-killing solution. It works by drying out the plant cells and killing the weed.
How to use:
- Identify the exact types of weeds in your yard. The younger and more vulnerable they are, the easier it is to eliminate them.
- Gather your supplies: a spray bottle, water, and a type of household vinegar with a minimum acetic acid concentration of 11%. Use caution when handling anything with a higher concentration. If misused, it can cause blindness and severe skin burns.
- Mix 1 part vinegar with 1 part water to dilute the vinegar and pour it into the sprayer. Spray the entire plant, focusing on the base.
- Repeat as necessary.
- Alternative solutions include mixing 1 part baking soda with 2 parts vinegar or equal parts vinegar and dish soap. Follow the above-mentioned instructions.
Citrus oil solution
Type: Contact, post-emergent weed killer
If you’re a fan of essential oils, citrus oil can be an excellent weed-killer alternative to more traditional methods. This type of oil is derived from grapefruits, lemons, and oranges and can naturally eliminate weeds by killing the cells within the plant.
How to use:
- Make sure the weeds you’re targeting are young and tender.
- Purchase pure citrus oil and dilute 1 to 2 tablespoons with about 1 gallon of water to protect the soil and surrounding plants. Pour the solution into a sprayer or watering can.
- Choose a dry, sunny day and apply the mixture to the base, stems, and leaves of the weeds in your yard. Coat them well and repeat if needed.
Corn gluten meal
Type: Pre-emergent weed preventer/suppressor
Corn gluten meal is an excellent DIY pre-emergent that is readily available. It works by inhibiting weed seed germination and plant development. It’s best if you know what weeds grow in your area and apply it before they sprout.
Apart from its weed-suppressing qualities, corn gluten meal is also a great nitrogen source, beneficial for soil health.
How to use:
- Do your research before application and time it just right. Find out when weeds germinate in your area. Usually, this is in early spring or fall.
- Check the label instructions for application rates, considering your yard size. Stick to 20 pounds of corn gluten meal per 1,000 square feet of property.
- Purchase or rent a broadcast or hand spreader to apply the product evenly and cover the entire area.
- If possible, time the application around rainfall. Otherwise, water your yard to activate the gluten and create the weed-inhibiting barrier (it’s best to do it within five days). The recommended amount is between ¼ to ½ inches of water. Once you’ve done this, don’t water again, as the weed prevention process needs a dry spell to be successful.
FAQ about all-natural and organic weed killers
Where can I purchase all-natural or organic weed control?
These products are available for purchase online or at home improvement stores and garden centers. If you make your purchase online, read the detailed product description to make sure it’s organic, all-natural, or eco-friendly. It’s also a good idea to look at reviews to get an idea about its effectiveness. If you’re purchasing in-store, ask customer service about certifications.
Can all-natural or organic weed killers harm my soil?
Only if they contain high concentrations of sodium chloride (salt). Using salt-based herbicides on a regular basis can lead to soil salinization, which means that there’s excessive salt buildup in the soil. It also can reduce soil fertility, interfere with microbial activity, damage your plants, and leach into nearby water sources. Use salt-based weed killers carefully, following the recommended rates and monitoring your yard closely.
Are there any other all-natural or organic weed preventers?
Mulch is another excellent option to keep those weeds from sprouting and destroying your curb appeal. You can keep weeds at bay anywhere in your yard by spreading about 3 inches of mulch over the designated area (flower beds, vegetable gardens, lawns). This will block the seedlings’ access to sunlight, killing them before they’ve had a chance to germinate.
What types of weeds do all-natural or organic weed killers eliminate?
All-natural or organic weed killers can effectively eliminate a variety of common weeds, particularly when used on young and actively growing plants. They can target any of the following:
- Broadleaf weeds (dandelion, clover, plantain, thistle, or purslane)
- Grassy weeds (crabgrass, quackgrass, or annual bluegrass)
- Annual weeds (chickweed, pigweed, or nettle)
- Perennial weeds (Canada thistle, bindweed, knotweed, dock, or ground ivy)
- Woody weeds (poison ivy, poison oak, English ivy, or bamboo)
- Sedges (purple or yellow nutsedge)
Let a pro do all the hard work
We’ve outlined the pros and cons of all-natural and organic weed killers and given you some easy homemade alternatives you can try. But if the DIY route just isn’t something you’d like to try, contact a local pro. In addition to helping you choose the right weed killer for your needs, they can apply it and provide tips and tricks for a long-term, weed-free yard.
Main Image Credit: Shutterstock
