How to Kill Weeds Naturally

A pristine, healthy lawn is important to many Americans. Did you know over 40 million acres of land in the continental US has some form of lawn on them? That’s three times more than corn or any other irrigated crop. 

Maintaining vibrant, deep-green grass throughout the growing season is a commitment, but it can be off-putting to budding lawn enthusiasts. Why? Well, mother nature can be unpredictable.

Weeds are one of the gardener's biggest enemies (aside from pests!). Having healthy grass in the first place can discourage weeds from competing with your lawn for light, air, and nutrients. If you’ve had enough of weeds, your impulse might be to reach for the herbicides. After all, it’s an easy and effective way to eliminate weeds. But harsh chemical herbicides, insecticides, and fungicides can pollute surrounding aquatic ecosystems — even the water we drink

If you’re set on using a herbicide, try one which is good for the environment. We recommend Mirimichi Green herbicide, a fast-acting organic weed killer to spot spray lawn weeds. It leaves no harmful residues and is readily biodegradable. 

For the even more eco-conscious, there are a few ways to kill weeds naturally — which can be a cheaper and safer option for residential lawns. Remember that fertilizers, biostimulants, and soil moisture managers can also help keep your grass in good condition. But, if you’re ready to declare war and kill weeds organically, we’ve devised some natural methods. 

Kill Weeds Organically

Most of the time, weeds indicate problems in your soil. Different weeds prefer specific environments where their particular needs are met. For example, ground ivy likes damp soil and shady areas, and other weeds like Annual Knawel enjoy acidic soil

Identifying the weeds that could destroy your lawn will give you a good idea of what’s under your grass. But, if you want to be more precise, use a home soil pH test kit to tell you whether your soil is too acidic or alkaline. A neutral pH is the way to go. Once you’ve recognized what you’re dealing with, it’s time to get stuck into killing weeds in the grass — naturally!


Biostimulants

As we’ve mentioned, having healthy, flourishing grass is a natural way to discourage weeds in your lawn. Plant biostimulants contain substances and microorganisms which work to stimulate biological plant processes. Biostimulants can enhance nutrient availability, assimilation efficiency, and tolerance to environmental stresses.

Release 901C™ - Biostimulant with Fertilize

 

Our recommendation? Release 901C™. It’s both fertilizer and biostimulant with NanoRelease™ Technology, providing a wide variety of nutrients to your turf. Release 901C™ contains micronized nutrients and carbon, which the plant can immediately absorb without breaking down nutrients. The 10% liquid carbon content creates aeration within the soil to drive more profound root growth and improve water retention and nutrient uptake. Release 901C™ can also serve as a catalyst to enhance other turf maintenance product performance. For avid lawn-enthusiasts, this is the ultimate fertilizer and biostimulant combination. 

For the more environmentally conscious, try Release ZERO™ liquid biostimulant by Mirimich Green and get effective, organic weed control.

Boiling Water & Heat

This is one of the simplest DIY methods to kill weeds organically. Bring some water to the boil and pour over weed stems and leaves. The temperature of boiling water shocks the weed leaves and seeps into the roots, killing the plant quickly. This is a helpful method of killing weeds in grass and cracks, sidewalks, or driveways.

One of the main advantages of boiling water is that it won’t leave any harmful residue, leaving the area you’ve treated ready for reseeding. 

TOP TIP: Apply boiling water only to weeds and not other plants. Water is water. It isn’t selective, so it can kill flowers and vegetables if you’re not careful. 

You’ve heard the phrase: “fight fire with fire” but did you know that you can also fight weeds with fire? Purchase a flame-weeder tool that will immediately wilt weeds and kill any resprouting weeds upon repeat applications. Fear not; flame-weeders are designed to target small areas directly, so you will not be setting the whole neighborhood on fire. Be sure to proceed with caution and avoid flame weeding during droughts or dry spells. It’s also worth checking if using a flame-weeder tool is legal in your state or area. 

Salty Solutions

Old wooden table with a Salt Shaker (close-up shot; selective focus)

Salt, also known as Sodium Chloride, is an effective herbicide. Salt affects plant photosynthesis, respiration, nutrient distribution, and absorption. Using salt can have a detrimental effect on your soil, displacing other mineral nutrients — which is why you should only apply it directly to weed leaves. 

The easiest way to apply salt to kill weeds organically is by making your own salt spray. Here’s how to make one:

  1. This method works best if you have an empty spray bottle on hand. They’re cheap to buy or transfer a household cleaning spray to another container. Ensure you wash the container thoroughly before use to avoid chemical contamination.
  2. First off, dissolve one part of salt in eight parts of hot water. You can make this solution stronger by adding one part to three parts water if you need to.
  3. Add a little liquid dish soap (around a teaspoon) to your mixture. This will help your salt spray stick to leaf surfaces. 
  4. Carefully pour your solution into your spray bottle. A funnel can make the job easier. 
  5. Now, you’re ready to apply your homemade weed killer. Spray only the leaves of weeds and stay clear of nearby plants you want to target. We recommend covering or tying back any plants that might get accidentally sprayed. 

TOP TIP: Don’t spray your mixture on cement driveways or sidewalks, as this formula can discolor them. 

White Vinegar

white vinegar on the wooden table top

White vinegar contains acetic acid, which dries weeds out. Again, this is a homemade herbicide to apply only to weed leaves. You can get white vinegar from your local grocery store, which contains around 5% acetic acid. This should be strong enough for most weeds, but you can get an industrial strength version from a garden supply store. 

Just like the salt spray, you can apply white vinegar similarly. But, you can apply it at full strength without dilution. Adding liquid dish soap will help the vinegar adhere to the leaves — but be careful not to overspray or target soil or other garden plants. 

Combining salt and vinegar also works. One part to a gallon of vinegar is an excellent ratio to adopt — with a little dish soap. 

TOP TIP: Wear protective equipment like goggles and gloves if you use industrial strength vinegar. 

Borax

Borax is sold as a cleaning and laundry product in many stores. It’s also an effective natural herbicide. Combine 10 oz of powdered borax with 2.5 gallons of water, mix thoroughly and apply using a spray bottle. Avoid contact with bare skin and eyes; try not to saturate soil or plants with your borax solution. 

Killing Weeds in Grass — Your Way!

A hand-weeder tool is one of the more obvious methods for eliminating weeds from your lawn. This is ideal for the odd weed or two growing on small lawns and hand-weeders can get right to the root. Check out our recent blog post for a step-by-step guide on hand-weeding and more information on weed control. 

To achieve a golf course lawn, you’ll need to do more than keep it free from weeds. Topdressing, watering, and mowing are also key parts of lawn maintenance. If your weed problem is out of control, some of these natural methods might not be enough. If this is the case, look at some of the best products for killing your weeds without killing your grass.


Golf Course Lawn Store stocks a wide selection of herbicides and lawn-care products to help you achieve perfect grass. Browse our selection, or subscribe to our YouTube channel for lawn-care tips and tricks.